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CHEMISTRY AND CHEMICAL ENGINEERING.

Chair: Ken S. Lee, Jackson State College

Vicechair: Lovell E. Agwaramgbo, Tougaloo College

THURSDAY MORNING

Emerald Room

9:00 THE INVESTIGATION OF SODIUM L-ACYLN-GLUTAMATE / CATIONIC CELLULOSE INTERACTION

Naoya Ymato [1][*] Rebecca Boudreaux [2], and Robert Y. Lochhead [2], (1.) AminoScience Laboratories Ajinomoto Co., Inc., Kanagawa 210-8681 Japan and (2.) University of Southern Mississippi Hattiesburg, MS 39406

The interaction of Cationic Cellulose with anionic surfactants has been well documented. The objective of this study was to investigate the interaction of Cationic Cellulose with sodium L-Acyl-N-Glutamate. Phase diagrams were constructed to examine the interactions in the concentrated surfactant regime. The Cationic Cellulose reduced the range of the clear composition and this is attributed to the crystallization of the surfactant due to osmotic competition for water. Phase diagrams were prepared at low concentration, in the region of the surfactant's cmc. A complex precipitated in the vicinity of the cmc but redissolved at higher surfactant concentrations. Surface tension measurement indicates that below a certain surfactant concentration, no binding to polymer occurs, but at a critical concentration there is an exceptional uptake of surfactant by polymer, followed by plateau region.

9:15 SOLVENT EFFECTS ON THE PHOTOPHYSICS OF MODEL ARYL CINNAMATE CHROMOPHORES

Rabih O. Al-Kaysi [*] and David Creed, University of Southern Mississippi, Hattiesburg MS 39406-5043

Several compounds were synthesized to model the aggregation properties of liquid crystalline polymers in which aryl cinnamates act as both chromophores and mesogens. Model compounds such as 1 have two aryl cinnamate chromophores attached to a rigid norbornane skeleton. The orientation of these chromophores with respect to one another can be determined or estimated. Model compound 2 is a reference chromophore for 1. The UV-VIS spectrum of compound 2 in hexane has a [[lambda].sub.max] 289 nm. Addition of 1 % ethanol shifts the [[lambda].sub.max] to 312 nm. This behavior suggests aggregation of 2, through hydrogen bonding, which perturbs the UV-VIS spectrum. Addition of ethanol presumably disrupts hydrogen bonded dimers. We were not able to obtain the spectrum of compound 1 in hexane due to its very low solubility. It has [[lambda].sub.max] = 310 nm in chloroform and 318 nm in ethanol.

9:30 THE EFFECTS OF GRAVITY ON POLYMERIC FOAMS PRODUCED THROUGH FREE-RADICAL FRONTAL POLYMERIZATION: RESULTS FROM THE NASA REDUCED GRAVITY STUDENT FLIGHT OPPORTUNITIES PROGRAM

William J. Ainsworth [*], Vinh V. Nguyen, James R. Warren, Paulin N. Wahjudi, Monique Kendrick, Felicia Stewart, and John A. Pojman, University of Southern Mississippi, Hattiesburg, MS 39406

Through the use of frontal polymerization, a new process has been developed for the production of polymeric foams. The addition of a low-boiling point blowing agent to a frontal polymerization system at constant pressure results in the production of a polymeric foam. This process utilizes the thermal energy produced by the forming polymer to cause the blowing agent to be vaporized behind the front to produce bubbles, which become trapped in the forming polymer. To investigate the effects of gravity on polymeric foams produced through this method, experiments were performed aboard the NASA KC-135A reduced gravity aircraft. Changes in foam density, front velocity, bubble size, and bubble distribution were examined and compared to the results from ground based experiments.

9:45 PHASE BEHAVIOR OF HYDROPHOBICALLY MODIFIED POLYELECTROLYTE/SURFACTANT SYSTEMS

Rebecca Boudreaux [*], Stacey V. Maggio, and Robert Y. Lochhead, University of Southern Mississippi, Hattiesburg, MS 39406

The properties of polymer-surfactant solutions are governed by a fine balance between hydrophobic, hydrophilic, and ionic interactions. It is expected that the control of the hydrophobic and ionic character of a given system will allow for the precise control of desired liquid crystalline phase behavior. This research is aimed at the control of hydrophobic and ionic character through the use of hydrophobically modified polyvinylamine (HMPVAm) which allows for the precise control of hydrophobic content and charge density. By controlling ratios of hydrophobic content and charge density, it is expected that the fine-tuning of desired liquid crystalline phases can be achieved. Binary phase diagrams were constructed for three polymer systems: unmodified polyvinylamine, HMPVAm-0.4%, and HMPVAm-0.8%. An induced hexagonal phase in dodecyltrimethyl ammonium bromide (DTAB) was observed for all of the polymer systems as polymer concentration increased. The hexagonal phase appeared at lower surfactant concentrations as the pH increased in the presence of unmodified polyvinylamine. It is proposed that the induced phase behavior is due to an osmotic competition for solvent rather than direct polymer-surfactant interactions. The control of liquid crystalline phase behavior is achieved in this study by altering pH, degree of hydrophobic modification, and surfactant concentration.

10:00 THE EFFECTIVE INTERFACIAL TENSION IN MISCIBLE FLUIDS

Vitaly Volpert [1], Thierry Dumont [1], Yuri A. Chekanov [2], Jonathan Masere [2], and John A. Pojman [2], (1.) Universite Lyon I, 69622, Villeurbanne Cedex, France and (2.) University of Southern Mississippi, Hattiesburg, MS 39406

Using the concept of the Korteweg stresses induced by concentration and temperature gradients, we show with numerical simulations that convection should occur in miscible systems with sharp but non-uniform concentration gradients, analogous to Surface-Tension Induced Convection in immiscible fluid layers. We attempted to observe such convection in low g caused by radial concentration gradients in propagating fronts of benzyl acrylate and hexyl acrylate polymerization but found that the variations in the acceleration were too large. However, studying model systems of glycerin in water showed that on the time scale of seconds, miscible and immiscible fluids are indistinguishable.

10:15 Break

10:30 INFLUENCE OF THE TYPE OF HYDROPHOBE ON THE ASSOCIATION BEHAVIOR OF HYDROPHOBICALLY MODIFIED CATIONIC POLYMER

Nad'a Spisakova [*] Robert Y. Lochhead, and Stacey V. Maggio, University of Southern Mississippi, Hattiesburg, MS 39406

A complex association behavior of hydrophobically modified polyvinylamine was investigated. Understanding of the behavior of a model synthetic polymer can be very useful in applying to more complicated biological systems, where self-association is very common. The polyvinylamines modified to different degree with bulky and linear-alkyl chain hydrophobes were synthesized. The synthetic route comprised the synthesis of polyvinylformamide, the hydrolysis to polyvinylamine and finally the hydrophobic modification of polyvinylamine. The polymers were characterized via NMR and static light scattering. Their behavior in water was studied by means of pyrene fluorescence spectrometry and rheology. It was shown that at 0.8 mol% of hydrophobes on the polymer backbone, the linear hydrophobes caused strong intermolecular associations, due to which the viscosity of the solutions rose substantially. The effect of bulky hydrophobes differed in extent compared to linear hydrophobe. The formation of micelles in each case was proved by the changes in the pyrene emission spectrum-finger print region. The influence of the net charge on the solution behavior by variation of the pH is also shown.

10:45 PHOTOCHEMISTRY AND PHOTOPHYSICS OF A SIDE-CHAIN LIQUID CRYSTALLINE POLYMER

Alline P. Somlai [*] and David Creed, University of Southern Mississippi, Hattiesburg, MS 39406

A trans-4,4'-dialkoxystilbene containing liquid crystalline polymer having nematic and smectic phases has been irradiated as an "as cast" film, as an annealed film, and in solution. The occurrence of 2+2 photocycloaddition of the stilbene moiety upon irradiation of the films at 313 nm is seen by the decrease in the stilbene absorption above 300 nm and the appearance of a cycloadduct absorption band at 280 nm. Some stilbene-like absorption is regenerated when the 313 nm irradiated 'as cast' film is subsequently irradiated at 254 nm. This apparent photoreversibility is not observed with the annealed film. In solution, irradiation of the polymer at 366 nm and 313 nm induces 2+2 cycloadduct formation. It is necessary to perform all experiments under [N.sub.2] to avoid formation of other photoproducts. The fluorescence quantum yield of the polymer was estimated using the standard, trans-stilbene, with a literature value of 0.05. The polymer and standard have roughly the same quantum yield in [CHCl.sub.3].

11:00 PREPARATION OF POLYMER MATERIALS VIA FRONTAL POLYMERIZATION

Yuri A. Chekanov [*], and John A. Pojman, University of Southern Mississippi, Hattiesburg, MS 39406

Frontal polymerization is a self-sustaining process in which a localized reaction zone or front propagates through a monomer converting it to the polymer. High exothermicity of the polymerization reaction and Arrhenius dependence for the polymerization rate are the most important requirements for a monomer to support a front. The formation of polymer material was accomplished by ascending frontal polymerization in a cylindrical reactor. It was realized by continuous fed of liquid monomer on the top of the front. This approach offers an excellent opportunity to create any type of gradient in the polymer by simply changing the composition of the monomer feedstream. A range of surface velocities supporting front can exist for the ascending mode, which we call its dynamic range. The dynamic range for tri(ethylene glycol) dimethacrylate cured with tricaprylmethylammonium persulfate initiator was determined experimentally. Polymer samples with hyperbolic gradient of dye were prepared by the method developed as pro mising materials for optical limiters.

11:15 FLUORESCENCE STUDY OF ASSOCIATION BEHAVIOR OF HYDRPOHOBICALLY MODIFIED CATIONIC POLYMER IN WATER

David A. Presken [*], Robert Y. Lochhead, Nad'a Spisakova, and Stacey V. Maggio, University of Southern Mississippi, Hattiesburg, MS 39406

Association behavior of polymers can be influenced by many factors. The knowledge of Their relationship gives us valuable tool for designing industrial applications. Fluorescence technique was used to characterize the association behavior of hydrophobically modified polyvinylamine. This molecule is a model for self-associating behavior based on charge-charge repulsion and hydrophobic interaction. The polyvinylamine bearing 0.8 mol% of bulky hydrophobe was studied. Its behavior is compared to polyvinylamine hydrophobically modified with C12 linear alkyl chain, which was reported previously. The polymers were characterized via NMR and static light scattering. The formation of micelles in each case was proved by the changes in the pyrene emission spectrum-finger print region. As pyrene experiences hydrophobic environment, its ratio of the peak intensity at ca. 373 nm and at ca. 383 urn decreases. At 0.8 mol% of hydrophobes on the polymer backbone, the linear hydrophobes caused strong intermolecular associations , which could be seen on the high apparent viscosity of the solutions. However, fluorescence technique cannot estimate the portion of inter vs. intramolecular associations. The influence of the net charge on the micelle formation by variation of the pH is documented.

11:30 INVESTIGATIONS OF EXPANDING SPHERICAL FRONTS

John A. Pojman and Marcus Molden [*], University of Southern Mississippi, Hattiesburg, MS 39406

The expansion of spherical fronts of a frontal polymerization system in which spin modes migrate around the front as it propagates is under investigation. Frontal polymerization involves the conversion of a monomer into polymer via a localized reaction zone that propagates. For this study, reaction solutions consisting of dimethlysulfoxide (DMSO), pentaerythritol triacrylate (PET3A) monomer, and ammonium persulfate as initiator were used. The purpose of this study is to determine the behavior of fronts as they propagate from the center of a sphere outwards. To prevent sedimentation of the polymer during the reaction, Cab-O-Sil, ultra-fine silica gel, has to be added to the reaction solution to make it more viscous. Photoinitiation, a less invasive approach than thermal initiation, is used. A photoinitiator, Irgacure 184, is injected at the desired initiation site and by shining UV light, initiation of the reaction is achieved.

11:45 Divisional Business Meeting

THURSDAY AFTERNOON

Emerald Room

2:00 PLATINUM (II) VS. PALLADIUM (II): A DFT STUDY OF INTERACTION WITH GUANINE

Glake A. Hill, Jr. [*], Alexander Pelmenschikov, and Jerzy Leszczynski, Jackson State University, Jackson, MS 39217

Cisplatin (cis-[[Pt[([NH.sub.3]).sub.2]].sup.2+]) is one of the most widely used antitumor drugs. Although it has been studied in great detail, the mechanism of its antitumor activity is not yet completely understood. Our goal was to compare the binding properties of (cis-[[Pt[([NH.sub.3]).sub.2]].sup.2+]) and Cis (cis-[[Pt[([NH.sub.3]).sub.2]].sup.2+]) with respect to DNA bases. Using molecular models (structures 1 and 2) we have found that the two metals, and their subsequent compounds, are close in binding properties and induce analogous conformation changes in DNA. Our results allow for the conclusion that similar metals can act as adequate and maybe superior substitute for platinum.

Platinum with Bound Palladium with Bound

DNA DNA

2:15 ANOMALIES IN THE LIQUID CHROMATOGRAPHY OF AMINES USING SULFATED BETA-CYCLODEXTRIN AS A CHIRAL SELECTOR

J.C. Strawbridge [*], Kenneth McMurtrey, and J.G. McCoy, University of Southern Mississippi, Hattiesburg, MS 39406

Racemic DOPA, salsolinol (SAL), 1-carboxysalsolinol (1-CSAL), and cis-3-carboxysalsolinol (3-CSAL) were chromatographed using a conventional C18 reversed phase LC column. The mobile phases used included aqueous solutions with and without the chiral selector sulfated [beta]-cyclodextrin (S-[beta]-CD) and the ion pairing agent sodium heptyl sulfate (SHS). Analyses were conducted at temperatures from 0[degrees]C to 35[degrees]C to determine changes in enthalpies and entropies of retention. S-[beta]-CD appears to be an excellent chiral selector for all of the studied enantiomers, except those of 1-CSAL, which separates slightly only at 0[degrees]C. During these mobile phase and temperature dependence studies anomalies were present. Van't Hoff plots of ln(k') vs. 1/Tare linear between 0[degrees]C and 13[degrees]C, and again between 17[degrees]C and 35[degrees]C. Between 13[degrees]C and 17[degrees]C, a dramatic change in slope occurs. Enthalpy and entropy changes appear to be roughly constant irrespective of whic h mobile phase is used, and are taken to indicate conformational changes in the column's packing material. When using mobile phases containing SHS, a triplet peak was obtained for L-3-CSAL at 5[degrees]C. No other compounds, even D-3-CSAL, exhibited this behavior.

2:30 SEQUESTERING METAL IONS ONTO TIRE DERIVED PARTICLES

Eric R. Smith [*] and David L. Wertz, University of Southern Mississippi, Hattiesburg, MS 39406

Tire derived particles [tdp] from the WOMBAT process were mixed with samples of six aqueous solutions containing different dissolved metal ions. After one week, the tdp samples were collected from the solutions by gravity filtration and dried. X-ray fluorescence spectroscopy was run on each of the samples to determine its components. The purpose of the experiment is to determine if the tdp sequesters metal ions from the solutions. The X-ray spectrum shows a K-alpha and K-Beta peak for a metal ion such as copper if it is present in the sample. Attempts to remove the sequestered ions from the tdp by washing with water have been undertaken.

2:45 X-RAY CHARACTERIZATION OF POTENTIALLY AUXETIC LIQUID CRYSTALLINE ELASTOMERS

Chad J. Booth [*] and A.C. Griffin, University of Southern Mississippi, Hattiesburg, MS 39406-5043

While almost all known materials expand laterally when stretched, auxetic materials are those that contract laterally when stretched. The liquid crystalline (LC) materials examined in this study are composed of both terminally and laterally attached (transverse) rigid rods. These laterally attached rods rotate when stretched potentially causing an auxetic effect. Wide angle x-ray scattering (WAXS) is an excellent method to probe the interchain distance change upon stretching. Previously we have shown in similar linear LC systems that contain a transverse rod that upon stretching there is an increase in interchain distance. On the contrary, the elastomeric systems discussed in this paper seem to support Warner and Terentjev's s theory of soft elasticity in that, there is no change in interchain distance even to 400% extension. We wish to thank the NSF (DMR-9420843) for support of this work.

3:00 Break

3:15 ELECTRODEPOSITION OF COPPER/NICKEL ALLOYS AND OXIDES FROM THE TETRANUCLEAR ([[upsilon].sub.4]-O)[{N,N-DIETHYLNICOTINAMIDE}.sub.4][Cu.sub.4-x][(Ni([H.su b.2]O))].sub.X][C1.sub.6] (x 0-4) COMPLEXES. SURFACE AND ELECTROCHEMICAL CHARACTERIZATION

Bizuneh Workie, Jackson State University, Jackson, MS 39211

Potentiostatic hydrodynamic electrodeposition at a Pt electrode form the heterotetranuclear complexes ([[upsilon].sub.4]O)[(denc).sub.4][Cu.sub.4-x][(Ni([H.sub.2]O)).sub.X][Cl.su b.6] (denc = N,N-diethylnicotinamide and x = 0-4) in 0.20 M tetrabutylammonium hexafluorophosphate/dimethyl sulfoxide results in a well adhering, continuous and microscopically rough surfaces. The potential necessary for the deposition is essentially the same for all complexes. Energy dispersive x-ray (EDS) study of the deposited films shows that the CuNi atomic ratio is the same as the metal stoichiometry of the complexes. X-ray diffraction (XRD) analysis reveals that the films deposited from the ([[upsilon].sub.4]-O)[(denc).sub.4][Cu.sub.4-x][(Ni([H.sub.2]O)).sub.X][Cl.s ub.6] (x = 1-4) are composed of Cu/Ni alloys. The Ni alloy composition determined by the XRD increases from about 12% for the ([[upsilon].sub.4]-O)[(denc).sub.4][Cu.sub.3]Ni([H.sub.2]O) to about 62% for ([[upsilon].sub.4]-O)[(denc).sub.4][(Ni([H.sub.2]O)).sub.4]. Particle size study of the Cu/ Ni alloys using XRD indicates that increasing the nickel content of the deposit leads to a deposition of finer grain alloys.

3:30 RESOLUTION OF THE ENANTIOMERS OF MAMMALIAN ALKALOIDS USING CHIRAL HPLC WITH SULFATED [beta]-CYCLODEXTRIN AS A MOBILE PHASE ADDITIVE

Kenneth McMurtrey [*], J.C. Strawbridge, T.M. Coleman, and J.G. McCoy, University of Southern Mississippi, Hattiesburg, MS 39406

The mammalian alkaloids salsolinol (SAL), tetrahydropapaveroline (THP), and tetrahydroxy-berbine (THB) are implicated as possible agents in the etiology of alcoholism or its symptoms. To develop methods to determine stereochemistry of the substances in intact animals we have investigated the use of HPLC with sulfated [beta]-cyclodextrin as a chiral selector in the mobile phase. Enantiomers of SAL, THP, and THB are well separated with selectivity ([alpha]) values of as much as 1.6 and measured resolution ([R.sub.s]) of 5.5. In contrast, the enantiomers of their methoxy analogs, salsolidine, tetrahyropapaverine, and xylopine, respectively, resist separation. Apparently the hydroxyls present in the mammalian alkaloids and absent in their methoxyl analogs play a role in binding to the chiral selector.

3:45 COMPARISONS OF WAVELENGTH DISPERSIVE X-RAY SPECTRA FROM MODEL COMPOUNDS DESIGNED TO SIMULATE SCRAP TIRES AND WOMBAT TIRE-DERIVED PARTICLES

Ashley D. Trahan [*] and David L. Wertz, University of Southern Mississippi, Hattiesburg, MS 39406

Model compounds of various solid-state metal salts were prepared by thoroughly mixing the metal salt with graphite. The samples were prepared by mass percent and ranged from 1-5% analyte by mass, which corresponds to the abundance range of each analyte in tires. A wavelength dispersive x-ray fluorescence (WDXRF) spectrum of each mixture was obtained using aRigaku x-ray spectrometer and an end-centered rhodium x-ray tube for excitation. The linearity of the relationship between peak intensity and analyte abundance has been explored for each of the analytes, and then this linearity has been used to measure the abundance of that analyte in the various scrap tire products being produced in the Wertz laboratory.

4:00 AUTODETACHMENT SPECTROSCOPY AND DYNAMICS OF VIBRATIONALLY EXCITED DIPOLE BOUND STATES OF H2CCCK-

K. Yokoyama [1][*], G.W. Leach [2], and W.C. Lineberger [3],[1] Jackson State University, Jackson, MS 39217; (2.) Simon Fraser University, British Columbia, Canada V5A IS6; and (3.) University of Colorado, Boulder, CO 80309

The direct observation of the rotational fine structure levels of a vibrationally excited negative ion dipole-bound state is reported. Autodetachment resonances of [H.sub.2]CCC- were observed for the (2.) [A.sub.1]-(2.)[B.sub.1] transition in one quanta of [V.sub.6], [V.sub.4], and [V.sub.2] and two quanta of [v.sub.6] vibrational modes of the DBS. Rotational assignments for both the electronic ground state and an electronic excited state, the dipole-bound state (DBS) were performed. Based on an electron affinity of 14469 [+ or -] 64 [cm.sup.-1], the binding energy of the electron in the DBS is 170 [+ or -] 50 [cm.sup.-1]. The vibrational frequencies for [V.sub.2]. [V.sub.4], and [V.sub.6] of the DBS are directly determined to be 1965(1) [cm.sup.-1], 1117(1) [cm.sup.-1], and 221.447(2) [cm.sup.-1], respectively. The observed autodetachment resonances contain information about the detachment dynamics via the observed linewidths, and the departing weakly bound electron is best regarded as a function of the neu tral core vibrational motions. The detachment rate varies by an order of magnitude, depending on the type of normal mode excitation. In particular, motions along the dipole moment axis significantly enhance autodetachment, indicating that the dipole-bound state is unstable with respect to neutral core motion which modulates the absolute value of the dipole.

4:15 Divisional Poster Session

GC/MS ANALYSIS OF BOLL WEEVIL CUTICULAR WAX

Edwin Tullos [1][*], Jason Corbitt [1], Marcus Steele [1], Dennis Elmore [2], and Joe Mulrooney [2], (1.)Delta State University, Cleveland, MS 38733 and (2.)United States Department of Agriculture-Agricultural Research Services, Stoneville, MS 38776

The boll worm is the most damaging predator to cotton crops in the Mississippi Delta. The cuticle of the parent boll weevil is covered by a surface wax which represents a major barrier to pesticide transport across the insect/atmosphere interface. Since the surface wax has such a significant influence on the penetrability of pesticides, it is important that the composition of this wax is known. In our study, cuticular wax was extracted from the surface of laboratory-grown boll weevils by washing them with HPLC grade chloroform. A 0.2- mg wax sample was reacted with hexamethyldisilazine in hexane. A Hewlett-Packard Model 5890 gas chromatograph with a 5971 mass selective detector equipped with a Hewlett Packard 7673A autosampler and interfaced with an HP ChemStation was used in all analyses. This procedure produces a surprisingly detailed analysis of unfractionated cuticular wax. The primary constituents are fatty acids and saturated and unsaturated hydrocarbons.

RING-OPENING REACTIONS OF SILYL, STANNYL, & GERMYL EPOXIDES

Lovell Agwaramgbo [1], Jerzy Leszczynski [2], Ilya Yanov [2], and Eucharia Agwaramgbo [1,2][*], (1.)Tougaloo College, Tougaloo, MS 39174 and (2.)Jackson State University, Jackson, MS 39217

Theoretical calculations were done on compounds 1-4 in order to evaluate and compare the influence of silicon, tin, and germanium in directing ring-opening reactions of epoxides. Epoxide I serves as a control with both experimental and theoretical data. Epoxides 2-4 are very toxic for experimental work, therefore, theoretical calculations became the most viable method to study them, Since tin and germanium are more electropositive than silicon, their electron-withdrawing ability or inductive effect will be greater than that of silicon. Therefore, if epoxide opening is due to inductive effect, then epoxides 2 & 3 will undergo ring-opening at the position [alpha] to tin and germanium, respectively. However, if ring-opening is controlled by chelation, then the silicon which is smaller will chelate better with oxygen than tin or germanium, leading to ring-opening a to the silicon. Epoxide 4 compares the stannyl and germyl groups in directing the ring-opening of the epoxide. The results of these investigations will be presented. Funds for this project was provided by the NSF-CREST Grant. We thank Glake Hill, Jr. for his suggestions.

SOLVENT EFFECTS ON THE PHOTOOXIDATION OF 2-METHYL-2-BUTENOIC ACID

Jason A. Payne [*] and Kristina L. Stensaas, Millsaps College, Jackson, MS 39210-0001

The solvent effects on the mechanism of the photooxidation of 2-methyl-2-butenoic acid with singlet oxygen ((1.)[O.sub.2]) will be described. Deuterated benzene, methanol, and mixtures of methanol/water were investigated for possible stabilization of the proposed perepoxide intermediate due to polarity. These photooxidations were carried out in an NMR tube and the products were monitored using (1.)H NMR. The results indicate that the same products are formed regardless of the solvent utilized.

AB INITTO POST-HARTREE--FOCK STUDY ON THE ENERGETICS OF NUCLEIC ACID BASES PROTONATION AND THEIR PROTON AFFINITIES

Yevgeniy Podolyan [*], Leonid Gorb, and Jerzy Leszczynski, Jackson State University, Jackson, MS 39217-0510

Protonation of nucleic acid bases (B) is very important in many biochemical processes, i.e. enzymatic reactions, stabilization of triplex structures, etc., and also due to the fact that protonation can cause mutations in the DNA via mispairing of complimentary bases. All geometry optimizations were performed with the standard 6-3l+G(d,p) basis set at MP2 level of theory. The single point calculations were performed at the MP4(SDTQ)/6-31 +G(d,p)//MP2/6-31+G(d,p), MP4(SDQ)/6-31+G(d,p)//MP2/6-31+G(d,p) and MP2/6-311++G(d,p)//MP2/6-31+G(d,p) levels of theory. Gas-phase proton affinities were calculated as the negative of enthalpy of the process B + [H.sup.+] [rightarrow] [BH.sup.+]. In this study we performed the most systematic investigations of the relative stabilities of different protonated forms of all nucleic acid bases. The values of proton affinities have also been calculated and compared to the experimental values. For the first time the values of proton affinities were calculated taking into account the contributions of rare tautomers of cytosine and guanine and the ir protonated forms. The results of the calculations on the energetics of protonated bases are in very good agreement with the experimental data. The study of proton affinities has indicated that the inclusion of rare tautomers for cytosine and guanine in the study is very important for good consistence with experimental results.

PHOTODEGRADATION OF METHYL ORANGE INDUCED BY TITANIUM DIOXIDE (Ti[O.sub.2])

Regina Thomas [1][*] Tywanda Jefferson [1], Nodja Adams [2] and Ken S. Lee [1], (1.)Jackson State University, Jackson, MS 39217 and Hinds (2.) Community College, Raymond, MS 39154

Photodegradation of methyl orange in an aqueous solution was monitored by measuring the UV absorption of the solution. Methyl orange was dissolved in water and titanium dioxide was added into the solution. Then it was irradiated by Ultraviolet Visible light. A small portion of the solution was withdrawn every 10 minutes for measuring UV absorption at 462 nm. Absorption was gradually decreased as irradiation continued. The rate law of photodegradation of methyl orange is the first order for the concentration of the methyl orange and its rate constant at room temperature is 6.54 x [10.sup.-3] [sec.sup.-1]. When we saturated the solution with [N.sub.2] gas, its reaction rate constant decreased to 3.82 x [10.sup.-3] [sec.sup.-1]. However, when the solution was saturated with air by bubbling, the rate constant of photodegradation increased to 1.12 x [10.sup.-2] [sec.sup.-1].

STRUCTURE DETERMINATION OF 3-METHOXYESTRONE BY NMR SPECTROSCOPIES

Demetrice Davis [*] and Ken S. Lee, Jackson State University, Jackson, MS 39217

3-Methoxyestrone was prepared as a starting compound by converting 3-hydroxy group in basic methanol solution. It was reacted with bromoacetic ester and zinc (Reformatski Reaction) in order to add the ester group on the 17th carbon. Since the proton NMR spectrum of 3-methyoxyestrone has a multiplet at 2.9 ppm with two hydrogen in integration, it was unclear for us to assign it whether the alpha hydrogen on 16th carbon or the benzylic hydrogen on 10th carbon. We had conducted thorough NMR studies: (1.) H COSY, (13.) C decoupled, DEPT135, HCCOSY, and HCCOLOC, to assign every hydrogen and carbons. In conclusion, the spectra confirmed that a multiplet peak at 2.9 ppm is representing the benzylic hydrogen of 10th carbon. Peaks representing alpha hydrogen at 16th carbon is at 2.2 and 2.5 ppm. The carbons at 10th and 16th are at 29.6 and 35.8 ppm, respectively. Hydrogen and carbon at 7th carbon are at 2.3 and 43.9 ppm.

DFT AND MP2 QUANTUM MECHANICAL STUDY ON MOLECULAR STRUCTURE AND STABILITIES OF CARBOHYDRAZIDE AND ITS MONO AND DIMETHYL DERIVATIVES

Issac Orton, Aminatu Issaka [*], Ali Jabalameli, Ramaiyer Venkatraman, Andrzej Nowek, and Richard H. Sullivan, Jackson State University, Jackson, MS 39217

DFT (Becke3LYP) and MP2 correlated levels of theory were applied to study of molecular structure and stabilities of carbohydrazide [[([NH.sub.2]NH).sub.2]CO] and its methyl [[NH.sub.2][NHNH.sub.2][NCH.sub.3]CO] and dimethyl [[(NH.sub.2][NCH.sub.3]).sub.2]CO] derivatives. Double-dzeta 6-3-1 G(d,p) basis set were used. Potential energy surface search revealed ten mimimum energy forms (rotamers) for unsubstituted and dimethyl and eleven for monosubstituted carbohydrazide. Their relative stabilities vary depending on the number and type of intramolecular hydrogen bonds [NH...O and NH...N] present. The relative energies of rotamers range between 0 to 16 kcal/mol. The predicted values at DFT and MP2 levels are similar and differ (DFT values are larger) by less than 10 percent.

CONVERTING WASTE WOMBAT FLUID TO AMMONIUM NITRATE WHILE EXTRACTING THE ZINC FROM THE WOMBAT FLUID

Marty Hartzog [*] and David L. Wertz, University of Southern Mississippi, Hattiesburg, MS 39406

The WOMBAT process uses nitric acid to oxidize various components in tires while converting the tires into several final products -- steel, fibers, and tire-derived particles. After repeated processing, the oxidizing power of the nitric acid is sufficiently reduced so that the WOMBAT reactions cease to occur. At this point, the depleted nitric acid, which contains large amounts of aquozinc complexes and large amounts of solvated sulfate, has been reacted with solid ammonium carbonate to produce the reaction: [[NH.sup.+].sub.4] (aq) + [[NO.sup.-].sub.3](aq) [right arrow] [NH.sub.4][NO.sub.3](s) after removing the water from the beaker containing the reaction products. The carbonate ion is being used to precipitate the zinc from the solution by the reaction: [Zn.sup.+2] (aq) + [[CO.sup.-2].sub.3] (aq) [right arrow] Zn[CO.sub.3](s) because the solubility product constant for zinc carbonate is small.

CARBON MONOXIDE--INTERHALOGEN MOLECULAR COMPLEXES. THE HIGH-LEVEL QUANTUM MECHANICAL COMPLEMENTARIES STUDY

Ali Jabalameli [*], Issac Orton, Aminatu Issaka, Ramaiyer Venkatraman, Andrzej Nowck, and Richard H. Sullivan, Jackson State University, Jackson, MS 39214

Molecular complexes of OC and CIF and BrCl has been observed and characterized by microwave spectroscopy as linear species. Quantum mechanical high-level (MP2, MP4, coupled-cluster theory) computational methods predict a variety linear and nonlinear isomeric forms of the titled systems.

AB INITIO QUANTUM MECHANICAL STUDY ON MOLECULAR STRUCTURE OF [BH.sub.2]X AND [BHX.sub.2] (X F, Cl)

Aminatu Issaka [*], Issac Orton, Ali Jabalameli, Ramaiyer Venkatraman, Andrzej Nowek, and Richard H. Sullivan, Jackson State University, Jackson, MS 39217

The microwave spectrum of [BH.sub.2]X (X = F, Cl) has been recorded an intermediate in the reaction between diborane ([B.sub.2][H.sub.6]) and boron halides [BX.sub.3] in gas phase. Also, an existence of [BHF.sub.2] and BH[Cl.sub.2] Was suggested. In our study, we report results of molecular structure predictions of these species. DFT (Becke3LYP) and MP2 levels of theory were applied. Double-dzeta and triple-dzeta quality basis sets augmented with polarization functions 6-31 G(d,p) and 6-311 G(df,pd) were used. Overall good agreement of calculated rotational constants, bond lengths, and bond angles with experimental data (where available) was obtained.

SYNTHESIS, STRUCTURE AND SPECTROSCOPY OF TERNARY COPPER(II) COMPLEXES INVOLVING L-PROLINE AND L-OH PROLINE AND AROMATIC DIAMINES

Kiwana T. Thomas [1], Ramaiyer Venkatraman [1][*], Jeffery D. Zubkowski [1] and Edward J. Valente [2], (1.) Jackson State University, Jackson, MS 39217 and (2.) Mississippi College, Clinton, MS 39058

Structures and spectroscopic properties have been determined for the ternary Cu(II) complexes containing L-proline and L-OH proline and 4,7 dimethylphenanthroline and bipyridyl. The absorption spectra of the 1:1:1 systems exhibited a single d-d peak at around 600-610 nm (pH 6-8) and the band centered at ca. 300-320 nm due to charge transfer interaction between proline ring and diamines were observed in the near ultraviolet region. The complexes with L-proline and L-OH proline, [Cu(Ophen)(L-pro)([H.sub.2]0)] [NO.sub.3] (1), [Cu(Ophen 4,7diMe)(L-pro)([H.sub.2]0)] [NO.sub.3] (2), [Cu(Ophen)(L-OHpro)([H.sub.2]0)] [NO.sub.3] (3), [Cu(bpy)(L-OHpro)([H.sub.2]0)] [NO.sub.3] (4), and [Cu(Ophen 4,7diMe)(L-OHpro)([H.sub.2]0)][NO.sub.3] (5) were isolated as crystals and the structures were determined by the X-ray diffraction method. Complex 1 crystallizes in the monoclinic space group, P2(1)/n, with unit cell of dimensions a 7.1732(2) A, b = 21.296(10) A, c =12.293(6) A, [alpha] = 92.19(4)[degrees]. Complex 2 crystalliz es in triclinic space group, P1, with unit cell a = 7.053(3) A, b = 11.081(5) A, c = 12.835(7) A, [beta] = 86.31(4)[degrees], [alpha] = 88.66(4)[degrees], [gamma] = 82.18(3)[degrees]. Complex 3 crystallizes in orthorhombic space group, P2(1)2(1)2(l), with a unit cell dimension a = 6.781(2) A, b 13.258(4) A, c = 20.170(7) A. Complex 4 is monoclinic, P2(l), with a = 10.399(5) A, b = 6.923(5) A, c = 11.991(8) A, [alpha] = 96.23(5)[degrees]. Complex 5 is monoclinic P2(1) with a = 11.445(2), b = 6.931(2), c = 12.937(3), [alpha] = 100.05(2). The copper (II) ion in each complex is in a five coordinate, slightly distorted square pyramid geometry. The proline [beta]--CH and NH lie on the same side as coordinated water and the Cu-[OH.sub.2] distance [-2.382 A] in which [beta]-CH and NH lie below the pyramid base away from coordinated water. Additionally, copper is coordinated weakly by carboxyl oxygen from neighboring inequivalent complex trans to shorter Cu-[OH.sub.2], and the shorter C=O...Cu distance [-3.102 A] oppo site to the longer Cu-[OH.sub.2]. Uncoordinated nitrates are hydrogen bonded to coordinated and uncoordinated waters.

AN AB INITIO QUANTUM CHEMICAL STUDY ON XANTHOPTERIN

M.K. Shuklal [1], Ramaiyer Venkatraman [2][*], and Jerzy Leszcsynski [2], (1.) Banaras Hindu University, Varanasi-221005, India and (2.) Jackson State University, Jackson, MS 39217

Xanthopterin is a classical butterfly pigment found in nature. Also, human beings suffering from cancer exhibit elevated urinary levels ofxanthopterin. In the present work, HF and DET theoretical calculations applying standard 631++G(d,p) basis set have been carried out to investigate the tautomeric properties of the molecule. The transition states corresponding to the intramolecular proton transfer from oxo to the hydroxy form have also been studied.

REFORMATE GAS CLEAN-UP

Lois A. Zook, Delta State University, Cleveland, MS 38733

Awareness of the effects of greenhouse gases on the global climate, and the subsequent environmental legislation to reduce these gases, has resulted in a rekindled interest in hydrogen energy technologies. A fuel cell is an electrochemical device that converts hydrogen and oxygen into electrical energy. The proton-exchange membrane (PEM) fuel cell has been suggested as a potential replacement for the internal combustion engine because it is clean, energy efficient, and fuel flexible. The hydrogen gas can be stored on board or produced as needed from liquid fuels such as methanol, ethanol, or gasoline. Liquid fuels are more attractive to consumers, but the reformation reactions to produce hydrogen gas from liquid fuels produce by-products that can poison the fuel cell catalyst sites. One strategy to clean-up these reformate streams via partial oxidation will be presented.

BOUND STATES OF HOCI AND DOCI

Joseph A. Bentley [*], and B. Ramachandran, Delta State University, Cleveland, Mississippi 38733 and Louisiana Tech University, Ruston, Louisiana 71272

We report vibrational energies for the HOCI and DOCI molecules in the gas phase, calculated from ab initio and scaled ab initio potential surfaces. The ab initio calculations were performed at the CASSCF/MR-CISD levels of theory, using the highly polarized correlation consistent augmented Valence Triple Zeta (cc-pAVTZ) basis sets of Dunning. The multireference analog of the Davidson correction was used to approximate the effect of higher excitations (MR-CISD+Q). The Scaled External Correlation (SEC) method of Brown and Truhlar was used to extract additional dynamical correlation energy from both the MR-CISD (CI/SEC) and MR-CISD+Q (CI+Q/SEC) energies. The CI, CI+Q, CI/SEC, and the CI+Q/SEC energies up to 20,000 [cm.sup.-1] above the HOC1 minimum were fitted to polynomial expansions and the spectroscopic parameters evaluated in each case. These results are compared to those from the calculations of Koput and Peterson using significantly larger basis sets [Chem. Phys. Lett. 283 (1998) 139], the "complete basis set limit" results of Skokov et al. [J. Chem. Phys. 109(1998)2662], and to available experimental results. It is seen that applying the SEC scaling to CI or CI+Q energies obtained using a moderate basis set (ccpAVTZ) is a viable alternative to the use of extremely large basis sets.

DECREASED ANTIBODY CATALYTIC ACTIVITY ELICITED BY FLEXIBLE TRANSITION STATE ANALOG HAPTENS

Eric D. Helms [1][*], Amy L. Odenbaugh [2], and Brent L. Iverson [3], (1.) Delta State University, Cleveland, MS 38733; (2.) Duke University, Durham, NC 27708; and (3.) University of Texas at Austin, Austin, TX 78712

An aspect of catalytic antibody research that receives little attention in the literature involves those hapten systems that fail to elicit antibody catalysts despite a high affinity immune response and hapten designs that resemble those known to elicit catalysts. We found that six haptens of differing flexibility, in the form of three pairs of enantiomers, failed to induce any catalytic activity in rabbit polyclonal antibodies. This lack of catalytic activity occured despite high affinity and stereoselective immune responses against each of the haptens. Enantiomeric pairs are ideal for use in systematic hapten structure-activity studies, because the two enantiomers have identical physical properties in achiral environments. Nevertheless, the stereoselectivity inherent in the immune response generally leads to two different immunological solutions to recognition, one for each enantiomer. The surprising lack of observed catalytic activity with the enantiomeric haptens led to the investigation of a series of f ive benzyl phosphate haptens. Three different animal systems were investigated; New Zealand white rabbits, inbred BALB/cJ mice and outbred ICR mice. The elicited polyclonal antibodies displayed catalytic activity that was significantly weaker in terms of the level of observed catalytic activity, as well as frequency of elicited catalysts, compared to a more rigid phenyl phosphate hapten. In addition, the affinities of the polyclonal antibodies were significantly higher in the rabbits compared to the mice, yet the catalytic activity was generally higher in the murine systems. In two cases, polyclonal catalytic activity was only observed in mice, not the rabbits. Mechanistic studies indicated that there was not a change in rate-limiting step for hydrolysis of the benzyl substrates compared to the phenyl susbstrate systems. Thus, it appears as though the increased flexibility of the benzyl systems, not a change in mechanism, is responsible for their decreased ability to elicit antibody catalysts. Taken together, our results indicate that hapten flexibility should be avoided when designing transition state analogs for use in eliciting highly active antibody catalysts.

PROBING THE FUNCTION OF RNA-BINDING SITES OF TRANSCRIPTION FACTOR RHO BY ALKYLATION OF CYSTEINE RESIDUES

Larrious E. Collins [1][*], Brandt R. Burgess [2], and John P. Richardson [2], (1.) Alcorn State University, Alcorn State, MS 39096 and (2.) Indiana University, Bloomington, IN 47405

To understand more about mechanism of action of a protein factor from bacteria called Rho that causes termination of transcription at the end of genes and at regulatory sites. My experiments are to explore the role of two residues in the function of Rho. One residue, which is normally a serine residue at position 82, is in the primary RNA-binding sites. The second residue is normally a seine at position 325. I have functional mutational derivatives of Rho in which these residues are changed to cysteine residues. I made derivatives of these proteins in which their cysteine residues have been modified with iodoacetamide, iodoacetic acid, and assayed for poly (C)-dependent ATP hydrolysis. Also, a form of Rho with no cysteine residue will be used as a control group for both residues. With the 82C Rho, the modification causes very little change in the activities compared to the 0C Rho, indicating that it is insensitive to modification with iodoacetamide and iodoacetic acid. Unlike the 82C, there is a difference i n the modification of 325 C. The results show that the modification causes a great change in the activity when compared to the 0C Rho. Therefore the results indicate that the 325C Rho is very sensitive to modification with iodoacetic acid, but not as sensitive to modification with iodoacetamide. Since the modification with iodoacetic acid puts a negative charge on the modified residue, these inhibited results indicate that the function of Rho is inhibited by the presence of a negative charge at residue 325. My conclusion is that the backbone of the RNA, which has a negative charge, does not come in close proximity with residue 82 but does come in close proximity to residue 325.

DESIGN, SYNTHESIS, AND EVALUTION OF B/C/D-RING ANALOGS OF THE FUNGAL METABOLITE OF K-16 AS POTENTIAL COMPLEMENT INHIBITORS

Jared Gilmore [*], Tori Hill, and Robert Sindelar, Alcorn State University, Alcorn State, MS 39096; NIH NHLBI STIMS Cardiovascular Biomedical Research Program; and University of Mississippi, University, MS 38677

The complement system, a component of innate immune response in all vertebrates, is extremely important to host defense against infectious pathogens. It also serves to initiate the inflammatory response and directly kill and promote the phagocytosis of invading microorganisms. Because of the importance and vital roles of the complement system, a slight disturbance may cause a number of pathological conditions. This list includes infectious diseases, stroke, wound healing, autoimmune disease, rejection after xenotransplantation, and others. Since undesired activation of the complement system is common in these condition, understanding how this system is controlled and what causes it to misbehave has attracted in tense inters from both academic researchers and industry researchers seeking to develop effective complement inhibitors with therapeutic benefit. Funding: NIH.

THEORETICAL EVALUATIONS OF INERT GAS ATOMS IN MOLECULAR CAGES

Billy R. Booth [l][*], Willard Collier [2], Charles U. Pittman, Jr. [2], and Svein Saebo [2], (1.) Alcorn State University, Alcorn State, MS 39096 and (2.) Mississippi State University, Mississippi State, MS 39762

Structures have been optimized for [4]-prismane (cubane), [5]-prismane, [6]-prismane, and pentaasterane using several levels of theory. Then a proton or a noble gas atom was placed in the center of these cages, and the resulting endohedral complex was re-optimized. Ab initio calculations at the Hartree-Fock and Density Functional levels of theory with various basis sets were employed. The strain energy induced upon enclosing a noble gas atom was calculated by subtracting the total energy of the cage plus the isolated noble gas atom from the energy of the endohedral complex. Inserting a Helium atom introduced strain energies of 26.89 kcal/mol, 6.82 kcal/mol, 4.19 kcal/mol per Carbon-Carbon bond in the endohedral complexes of respectively at the B3LYP/6-311 g(d,p) level of theory. In conclusion, derivatives of the prismanes having [CH.sub.2] links between the top and bottom ring carbons have larger internal volumes, allowing larger inert gas atoms to be inserted. Thus, pentaasterane was predicted to exist with Helium, Neon, Argon, and Krypton inserted into the cage. Steric strain increased as the size of the endohedral atoms increased.

CHARACTERIZATION OF SEB BASED IMMUNOASSAY SYSTEM

Tommie Pittman [1][*], Giri Gokulrangan [2], Samadhi Vitharana [2], and George Wilson [2], (1.) Alcorn State University, Alcorn State, MS 39096 and (2.) University of Kansas, Lawrence, Kansas 66045

An ELISA based immunoassay has been developed for characterizing a toxic analyte Staphylococcal enterotoxin B(SEB). SEB is a 29 kDa protein with infectious properties and hasa potential of being used as a biological warfare agent. Rapid detection and quantitation of SEB is of significant interest from a bioanalytical and commercial perspective. A titration immunoassay was designed and performed to determine the avidity pf a polyclonal rabbit (Rb) anti-SEB antibody for SEB. Affinity purification of the polyclonal anti-SEB IgG sample was performed using a reatigel 6X agarose column. An apparent [K.sub.f] the thermodynamic formation constant, was determined to be about [10.sup.8] [M.sup.-1] for an anti-SEB antiserum sample. Avidity of the affinity purified anti-SEB IgG sample was also calculated and found to be [10.sup.9] [M.sup.-1].

ANTIBODY IMMOBILIZATION TO HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC SUPPORTS: CHARACTERIZATION OF MAXIMUM ANTIBODY LOADING

Arniee Jackson [*], William Clarke, and David S. Hage, Alcorn State University, Alcorn State, MS 39096 and University of Nebraska, Lincoln, NE 68588-0304

This study examines the maximum extent of antibody immobilization that can be obtained on several HPLC-grade supports by Fab fragments as the model ligands. The pore size of the silica support varied in size and type. Three methods were used in this experiment. The first is the CDI method. It is achieved by coupling aldehyde groups on the support to amine or thiol groups in the protein. Six samples were analyzed using the CDI method. The pore sizes ranged from 50 A to 4000 A. The second method is schiff base. The schiff base method couples the protein to the aldehyde groups on the silica surface through the amine group contained in the protein. Three samples were analyzed using the schiff base method. The pore size ranged from 100 A-4000 A. The third method is tresyl chloride. The tresyl chloride method is site specific for sulfhydryl groups produced during the digestion of IgG with papain. Three samples were analyzed using the tresyl method. The pore sizes ranged from 500 A-4000 A. The conditions used in thi s study involved using an IgG concentration of 20.0 mg/ml in order to ensure enough protein present for at least monolayer coverage of the support silica particles.

A NOVEL ROUTE TO BISANOMERIC SPIROKETALS

Kesmic Jackson [*] and Keith Mead, Alcorn State University, Alcorn State, MS 39096 and Mississippi State University, Mississippi State, MS 39762

Spiroketals are compounds which occur in nature are known for their strong antitumor activity. The purpose of this experiment is to synthesize a bisanomeric spiroketal with exclusive equatorial substitution on the C2 and C8 carbons. It is believed that this substitution can be accomplished by protecting the axial site on the C2 carbon using a benzoyl group that would be bonded to the C8 carbon.

ANALYSIS OF THE CAFFEINE CONTENTS OF COMMERCIAL BRANDS OF INSTANT COFFEE

Caffeine is a stimulant of the central nervous system and is present in coffee, tea, cola drinks, cocoa, chocolate, wake-up pills and some headache and cold medicines. While low to moderate consumption of caffeine may have some beneficial health effects, taken in large doses, it can cause adverse health effects such as headaches, nervousness, rapid heartbeats, and convulsions. In this study we have developed a simple and convenient method based on ultraviolet spectrophotometric analysis for the quantitative measurement of caffeine in samples of commercial brands of instant coffee.

Abul B. Kazi, William C. Mahone, and Jermel Harris [*], Mississippi Valley State University, Itta Bena, MS 38941

INCORPORATION OF 7-AZAINDOLE INTO DNA AND STUDY OF ITS FLUORESCENCE PROPERTIES

Ke Wang, Sandra Stringfellow [*], Kanyetta Wilson, and Hongtao Yu, Jackson State University, Jackson, MS 39217

Incorporation of various modified DNA bases in place of a natural base of duplex DNA has been used in many research areas. Such "bases" as nonhydrogen bonding benzene, naphthalene, and indole analogues, as well as modified natural nucleic acid bases have been used for studying various biological events, nucleic acid structure and dynamics, and even for using them as potential anticancer/antibacterial drugs. For this reason we conducted the synthesis shown below. The overall yield for the 4-step synthesis was 28. The structures of all compounds were confirmed by proton and/or phosphorous NMR and high resolution mass spectrometry. Compound 4 is successfully used to incorporate 7-azaindole into DNA on an automated DNA synthesizer. DNA melting studies is used to compare the stability of DNA oligomers containing 7-azaindole and native DNA duplexes. Fluorescence emission intensity of 7azaindole in the nucleoside is 23 times enhanced than it is free in solution. The fluorescence of 7-azaindole in duplex and single stranded DNA is greatly quenched. This research is supported by an NIH-MBRS grant #S06GM08047.

FRIDAY MORNING

Emerald Room

9:00 THE MECHANISM OF DECOMPOSITION OF DIBENZYL TRISULFIDE 1-OXIDE

Arnold S. Brownell [*] and Kristina L. Stensaas, Millsaps College, Jackson, MS 39210-0001

The oxidation of dibenzyl trisulfide utilizing metachloroperoxybenzoic acid will be discussed. The initial product, dibenzyl trisulfide 1-oxide, readily decomposed at room temperature to produce a mixture of dibenzyl tetrasulfide and dibenzyl 1,1-dioxide disulfide. The decomposition reaction was monitored by following the benzylic protons in the (1.) H NMR spectrum. The mechanism of the decomposition of the 1-oxide will be discussed.

9:15 SYNTHESIS AND CHARACTERIZATION OF POLYAMPHOLYTES

Stephen Ray Jones [*] and Robert Y. Lochhead, University of Southern Mississippi, Hattiesburg, MS 39406

It is the objective of this research to develop polyampholyte materials and compare their solution properties with their polyelectrolyte counterparts as functions of both pH and ionic strength. Polyelectrolytes have large hydrodynamic volumes (thus large intrinsic viscosities) in deionized water; increasing salt concentrations collapse the chains. Polyampholytes tend to have collapsed conformations in deionized water due to electrostatic attractions; their conformations generally expand with increasing ionic strength of the solution. However, solubility and solution behavior of polyampholytes depends greatly on both the net charge and the charge distribution along the polymer chain. Polyampholytes generally become insoluble in deionized water as the cation to anion ratio approaches one. Target polyampholytes of interest are copolymers and terpolymers of diallyldimethylammonium chloride (DADMAC), acrylic acid (AA), and acrylamide (AA). Polyampholyte microstructure has been studied by (13.) C-NMR, H.=1-NMR, an d FTIR. Solubility behavior was examined using Hoy solubility parameters.

9:30 SYNTHESIS OF IONIC LIQUID-POLYMER ELECTROLYTE COMPOSITE MATERIALS BY FRONTAL POLYMERIZATION

Timothy F. Bourne [*], Jonathan Masere, Yuri A. Chekanov, and John A. Pojman, University of Southern Mississippi, Hattiesburg, MS 39406

Potentially highly conductive composites of polymers were synthesized by frontal polymerization. By utilizing the process of frontal polymerization, polymer composites with high salt percentages were synthesized while preventing macroscopic phase separation. The traditional process of batch polymerization was also employed to compare multiple properties of polymeric composites made. Ionic liquid salts were used in place of organic plasticizers for acrylate polymer matrices. Using a solution of ammonium persulfate in dimethyl sulfoxide as an initiator, self-sustaining polymerization fronts were realized at high salt:polymer ratios. Differential scanning calorimetry (DSC) studies show that the acrylte matrices exhibit neither glass transition behavior nor crystallinity of the polymer-salt composites as the composition of the salt additives increases.

9:45 POLYAMPHOLYTE ADSORPTION ONTO MONTMORILLONITE CLAY

Camille T. Haynes [*] and Robert Y. Lochhead, University of Southern Mississippi, Hattiesburg, MS 39406-0076

The objective of this project is to determine the mechanisms of interaction of model polyampholytes with montmorillonite clay as a function of solution pH and ionic strength. Polyampholytes used in these studies contain three types of monomers. Acrylamide will be used as an anionic spacer, 2-vinylpyridine as the cationic units and acrylic acid as the anionic units. The terpolymers are synthesized utilizing solution freeradical polymerization. Monomer incorporation is determined by monitoring characteristic peaks in (1)H and (13)C NMR spectra. Differences in ionic incorporation affect the solution properties of resultant polyampholytes. Electrostatic interactions between the clay surface and the charged units of the polyampholyte are an important driving force for adsorption. Interactions are affected by many factors, including pH and salt concentration of the solution and charge density of the polyampholyte. The interactions of ampholytic terpolymers are studied at differing solution pH and ionic strength. Th e polymer/clay colloidal systems are studied by adsorption isotherms, IR spectroscopy and gated decoupling (13)C NMR. This allows determination of the amount of polyampholyte adsorbed, which moieties are involved in adsorption, and the conformation of the adsorbed chains.

We would like to acknowledge Southern Clay Products for project funding.

10:00 A STUDY OF THE INTERACTIONS OF HYDROPHOBICALLY MODIFIED POLYVINYLAMINE WITH DODECYLTRIMETHYLAMMONIUM BROMIDE BY SURFACE TENSION MEASUREMENTS

Jennifer L. Smith [*], T. Susanne Smith, Stacey V. Maggio, and Robert Y. Lochhead, University of Southern Mississippi, Hattiesburg, MS 39406

The polymer-surfactant interactions of hydrophobically modified Polyvinylamine (HMPVAm) with Dodecyltrimethylammonium bromide (DTAB) in dilute solution have been studied using surface tension measurements. HMPVAm is a cationic polyelectrolye and DTAB is a cationic surfactant. The interactions were studied as a function of hydrophobe length, concentration, and pH. The two hydrophobes are heptyloxybenzoic acid and propoxybenzoic acid. 0.8% of the amine units on Polyvinylamine (PVAm) are altered by one of the hydrophobes. The polymer concentrations studied are 2.5 g/L and 10 g/L. The pHs studied are 3, 7, and 10. Neither of the HMPVAms are surface active due to strong self-association of the polymers. The critical micelle concentration (CMC) of DTAB increases in the presence of HMPVAm at all pH ranges and all concentrations. The surface tension measurements show that a non-surface active complex of surfactant absorbed onto polymer is formed when HMPVAm and DTAB are in solution. The different hydrophobes causes v ariations in the of the polymer/surfactant system, while increases in pH decrease the polymer/surfactant interactions. Similar trends are seen for both concentrations, and therefore concentration does not have a noticeable effect.

10:15 Break

10:30 ISOTHERMAL FRONTAL POLYMERIZATION: EXPERIMENTS AND THEORY OF METHYL METHACRYLATE SYSTEMS

Lydia L. Lewis.sup [1][*], Cynthia A. Spade [2], Paulin N. Wahjudi [1], John A. Pojman [1], and Vladimir A. Volpert [2], (1)University of Southern Mississippi, Hattiesburg, MS 39402 and (2)Northwestern University, Evanston, IL 60201

Isothermal frontal Polymerization (IFP) is a process which converts monomer to polymer through a localized propagating reaction zone. IFP propagation occurs due to the diffusive supply of species into a preformed swollen polymer region where the Trommsdorf effect is significant. The Trommsdorf effect accelerates the polymerization rate in the gel region over that in the bulk region, and the diffusion of the species from the bulk fuels the reaction. Even though IFP is used commercially to produce gradient materials, little has been published on the factors that promote and limit front propagation. We have examined the effects of the system temperature and the type and concentration of the initiator on the velocity and the distance travled by the front. We have also examined the effects of the viscosity of the preformed gel region on the front propagation. We have observed in methyl methacrylate polymerizations, both experimentally and theoretically, that higher system temperatures or faster-decomposing initiat ors yield fronts that travel faster but for a shorter amount of time. We have also observed that preswelled polymers of 20% or higher (weight of MMA as solvent/weight of PMMA) support propagation.

10:45 VISCOSITY STUDIES OF HYDROPHOBICALLY MODIFIED POLYVINYLAMINE AND DODECYLTRIMETHYLAMMONIUM BROMIDE SOLUTIONS

T. Susanne Smith [*], Jennifer L. Smith, Stacey V. Maggio, and Robert Y. Lochhead, University of Southern Mississippi, Hattiesburg, MS 39406

This study was conducted to determine the interactions of hydrophobically modified polyvinylamine with surfactant dodecyltrimethylammonium bromide through increases or decreases in viscosities. The type of hydrophobe, as well as the pH of the systems and the concentration of the surfactant was varied. The polyvinylamine was modified to a percent modification of 0.8% using propoxybenzoic acid and heptylbenzoic acid as the hydrophobes. The pHs of 3, 7, and 10 were studied. The charge on the polymer chain decreases as the pH increases, leading to a decrease in viscosity. Upon the addition of the dodecyltrimethyl ammonium bromide, the viscosity of the solution increased at a pH of 3, but increased less with higher pH. This is believed to occur because of the formation of mixed micelles in the solution. As the pH and surfactant concentration increased the polymer assumes a more collapsed conformation, which results in the decrease in viscosity and perhaps the formation of unimolecular micelles where the hydrophob es are inside, limiting surfactant interactions.

11:00 TWO-DIMENSIONAL FRONTS

John A. Pojman and Monique Kendrick [*], University of Southern Mississippi, Hattiesburg, MS 39406

Snells Law was investigated using frontal polymerization in two-dimensional space. Frontal polymerization is the conversion of monomer to polymer through a high energy source such as heat. The use of frontal polymerization in a two-dimensional system requires a sustainable front to travel in both x- and y- directions. A system consisting of dimethyl sulfoxide (DMSO) and 1,6-hexanediol diacrylate (HDDA) with diethyl phthalate (DEP) and [(NH4).sub.2][S.sub.2][O.sub.8] as the thermal initiator was used and by varying the initiator concentration, different velocities were obtained. In a petri dish, two reaction mixtues with different initiator concentrations were placed one in each half of the dish. To prevent mixing, via diffusion, Cab-O-Sil (super-fine silica gel) was used as a viscosifier. The reaction was ignited at the center and the subsequent front velocities and the curvatures in each of the two media monitored. By using the different velocities and curvatures, it was demonstrated that frontal polymeriza tion can conform with Snells Law.

11:15 RHEOLOGICAL BEHAVIOR OF HYDROPHOBICALLY MODIFIED CATIONIC POLYMER IN WATER

Derek Dorman [*], Nad'a Spisakova, Robert Y. Lochhead, and Stacey V. Maggio, University of Southern Mississippi Hattiesburg, MS 39406

Self-association phenomenon is employed in number of industrial applications and has been paid wide scientific attention. The factors that influence the solution behavior of the self-associating polymer are numerous and the matter is very complex. The tendency towards intermolecular associations of hydrophobically modified polyvinylamine was studied by means of rheology in the low shear region. The polyvinylamine bearing 0.8 mol% of bulky hydrophobe was characterized via NMR and static light scattering. Its behavior is compared to polyvinylamine hydrophobically modified with C12 linear alkyl chain to 0.8 mol%, which was reported previously. At 0.8 mol% of hydrophobes on the polymer backbone, the linear hydrophobes caused strong intermolecular associations, due to which the viscosity of the solutions increased. The bulky substituent shows fewer tendencies towards intermolecular interactions. The influence of the net charge on the micelle formation by variation of the pH is documented. At high pH, the polyelec trolyte chain adopts more collapsed conformation. This influence is superposed by the hydrophobic interaction of different type of hydrophobe.

11:30 OPTICAL GRADIENT MATERIALS PRODUCED VIA LOW-TEMPERATURE ISOTHERMAL FRONTAL POLYMERIZATION

Jonathan Masere [*] and John A. Pojman, University of Southern Mississippi, Hattiesburg, MS 39406

Using a newly developed low-temperature polymerization technique, polymethyl methacrylate (PMMA) matrices doped with organic laser dyes and organic optical limiters were successfully prepared. This technique affords less tenuous temperature conditions than had been used before. Optical dyes and a thermally unstable initiator were dissolved in methyl methacrytate (MMA) solution and fed into a PMMA tube yielding radial gradients in the process. On the other hand, an axial dye gradient was observed when MMA was overlaid and polymerization effected from a dyedoped PMMA seed. In either case, polymerization reactions were observed as a result of interfacial-gel polymerization with the subsequent formation of spatial gradient distribution of the optical dye dopants. Low temperatures are desirable to eliminate thermal and photothermal degradation of temperature-sensitive dyes during the during polymerization. The preparation of longer polymer rods with organic optical limiter dye gradient materials can also be reali zed with the use of low-temperature polymerization.

11:45 AN INVESTIGATION OF ISOTHERMAL FRONTAL POLYMERIZATION WITH A WATER SOLUBLE MONOMER

Paulin N. Wahjudi [*] and John A. Pojman, University of Southern Mississippi, Hattiesburg, MS 39406

We investigated water-soluble polymers to determine if they would exhibit isothermal frontal polymerization and to determine their behavior. Isothermal frontal polymerization is a method of converting monomer into polymer through a localized propagating reaction zone utilizing the gel effect. Experiments were carried out with a system consisting of water-soluble monomer, water as solvent, and initiator. Systems using the monomers of methacrylic acid and 2-hydroxyethyl methacrylate were investigated by varying the ratio of the monomer to water, varying the concentration of the initiator, and varying the temperature.

FRIDAY AFTERNOON

Emerald Room

2:00 USE OF FENTON'S REAGENT FOR THE REMEDIATION OF WATERS CONTAMINATED WITH MOTOR OIL

Abul B. Kazi, William C. Mahone, and Shirley Turner [*], Mississippi Valley State University, Itta Bena, MS 38941

Motor oil is a complex mixture of hydrocarbons with other additives. Improper disposal of used motor oil and accidental release during transportation can contaminate surface and ground waters. Waters contaminated with motor oil can pose serious threat to human health and aquatic lives, because many of the components are suspected carcinogens and are resistant to biodegradation, particularly in anaerobic ground water environment. In this study we are investigating the effectiveness of Fenton's reagent, a combination of hydrgen peroxide and ferrous iron for chemical remediation of water contaminated with motor oil. Preliminary results indicate that Fentons reagent can be an effective tool for the removal of motor oil components from contaminated waters. Determination of the efficiency of the Fenton's degradation is based on a variety of analytical techniques, including gas chromatographic analysis and measurement of the reduction of chemical oxygen demand (COD). Optimization of the effects of reaction paramete rs such as concentrations of hydrogen peroxide and ferrous iron, reaction pH, and reaction time is being studied.

2:15 COMPLEXATION OF TETRACYCLINE WITH METAL ION

Wedad R. Hussein [*] and Christopher G. Walker, Jackson State University, Jackson, MS 39217

The tetracyclines, a group of broad-spectrum antibiotics are effective against aerobic and anaerobic, Gram positive and Gram negative bacteria. Tetracycline, although not the first to be discovered, is considered the parent of the group for nomenclature purposes, Tetracyclines have a common skeleton made of four fused six membered rings, (A, B, C, & D). One of these rings, the D, is aromatic. From its chemical structure and the presence of 4-acidic protons, tetracycline should be capable of forming complexes with metal ions. It has been suggested that metal chelation plays a role in the tetracycline antibiotic action. Three models have been suggested for the metal ion-tetracycline complex based on the potential coordination site. From computational calculations, we found that one of the three models is the most likely complex to be formed. Potentiometric titration of tetracycline with metal ions in the pH range 8-10 was performed to determine the stability of the complex.

2:30 AN ANALYSIS OF SALT BRIDGE FUNCTION IN SECONDARY ELECTROCHEMICAL CELLS

William C. Mahone, T. Parker, and S. Green [*], Mississippi Valley State University, Itta Bena, MS 38941

It has long been known that in order for an electrochemical cell to function an ion exchange mechanism called a salt bridge must be incorporated into the design. The salt bridge is necessary to preserve cell neutrality. Without an ion exchange mechanism, the half cells become polarized and the power output drops to zero. By the use of multiple salt bridges of identical configuration we are investigating the kinetic aspects of salt bridge configuration. These investigations have provided interesting insights into ion transport processes associated with cell power output.

2:45 SYNERGISTIC EFFECTS USING THE MACROCYCLIC ANTIBIOTICS VANCOMYCIN AND RISTOCETIN A IN CAPILLARY ELECTROPHORESIS

Brad Farris [*], Kellie Woodling, and Timothy J. Ward, Millsaps College, Jackson, MS 39210

Capillary electrophoresis (CE) is a powerful tool for chiral separations. Recently the macrocyclic antibiotics have been shown to be a powerful class of chiral selectors in capillary electrophoresis (CE). The macrocyclic antibiotics contain the types of functional groups and spatial arrangement that provide multiple enantioselective interactions. The glycopeptide antibiotics have been the most useful of the macrocyclic antibiotics. In this work, a mixture of the macrocyclic glycopeptide antibiotics were used as a chiral selector in a countercurrent CE process. Some of the solutes analyzed showed enantioselectivity only with ristocetin A, and some of the solutes had greater enantioselectivity with vancomycin. Using a mixture of vancomycin/ ristocetin A provided greater enantioselectivity than either chiral selector alone. Interestingly, it was found this effect was greatest for those solutes which exhibited better enantioselectivity with vancomycin than ristqcetin A. Those solutes that showed greater enantios electivity with ristocetin A did not show as great as an enhancement when vancomycin was added to the mixture.

3:00 ELECTROCHEMICAL DEPOSITION OF HEAVY METALS FROM COMPLEXES IN AQUEOUS SOLUTIONS

William C. Mahone, Abul B. Kazi, and N. Powell [*], Mississippi Valley State University, Itta Bena, MS 38941

In this investigation we look at the effect of complexation on the aqueous solubility of heavy metal salts in solution. Because complexes mask the metal it reduces the activity of the metal in solution. Therefore more salt must dissolve to satisfy the solubility product limitations. Subsequently we look at the reduction of heavy metals in solution by electro deposition. Upon conclusion we will make recommendations about the feasibility of the deposition process for general remediation of heavy metals in contaminated waste water.
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Publication:Journal of the Mississippi Academy of Sciences
Geographic Code:1USA
Date:Jan 1, 2000
Words:10705
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