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Sixteenth Annual Northeast Ohio Undergraduate Research Symposium

Poster Presentations 1 Lindsey Speare (KSU) 2. Elizabeth Amory (UA) 3. Yuliana Ospina Yepes (UA) 4. Ruth Eckman (UA) 5. Tristan LaCombe (NASA) 6. Ifeyinwa Okafor (KSU) 7. Khoa D. Tran (UA) 8. Allison Reardon (UA) 9. Mansi Peesapati (CWRU) 10. Adam Chan (UA) 11. Jacob Martin (CSU) 12. Tyler Galbraith (KSU) 13. S Scanlon (CWRU) 14. Tyler Knisley (KSU) 15. Dylan Valente (KSU) 16. Robert M. Walker (UA) 17. Corahgan Whipple (KSU) 18. Sam Tietjen (CSU) 19. Elizabeth Phinney (KSU) 20. Emily Williamson (KSU) 21. Andrew Scherer (CSU) 22. Lauren Syrup (KSU) 23. Erik Feeley (KSU) 24. Benjamin Bosela (CSU) 25. Anna Ellis (CSU) 26. Adam DeLong (NASA) 27. Kaylynn Cooper (CWRU) 28. Zachary Adams (CWRU) 29. Cagatay Yilmazoglu (UA) 30. Mario Alberto (CSU) 31. Quinton Wright (CSU)

32. Amanda Dershem (UA) 33. Alyssa Agler (KSU) 34. Grace Burkhart (CWRU) 35. Avery M Gould (UA) 36. Jose Luis Pena (UA) 37. Matthew Sunthimer (KSU) 38. Peter Howard (CSU) 39. Claire T Senger (UA) 40. Zoe Moore (CWRU) Victoria McLaughlin (CWRU) 41. Kristen Campobasso (KSU) 42. Zane Tolbert (UA) 43. Cole Harlow (NASA) 44. Stephen F. Adasonla (UA) 45. Theresa Nosel (NASA) 46. Walid Abuhashim (UA) 47. Jacob Duckworth (CSU) 48. Megan Elizabeth Yankulov (UA) 49. Melica Nikahd (NASA) 50. Alexandra Yungblut (KSU) 51. Tyler Leibengood (CSU) 52. Mickey Yu (CWRU) 53. Elijah Holder (KSU) 54. Naazneen Ibtehaj (CWRU) 55. Bradley Lockhart (CSU) 56. Alex Lovins (KSU) 57. Jason Vaughn (UA) 58. Rumbila Abdullahi( UA) 59.

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1) Polymer Emulsion

Lindsey Speare Kent State University Christina Robb Dr. Deña Agra – Kooijman Dr. John West Kent State University Research on electrospinning polymer fibers mixed with liquid crystal is not well explored. The goal was to find spinning conditions that orient fibers along a common direction, but along the way new information was discovered. We found that the polymer, polylactic acid (PLA) dissolves easily in 2,2,2 trifluorethanol (TFE) solvent than chloroform/acetone (3:1) which was the ratio used in Junren Wang’s research paper Morphology Tuning of Electrospun Liquid Crystal/Polymer Fibers. However, addition of nematic liquid crystal, E7 forms an emulsion instead of a solution. Under various spinning conditions, liquid crystal droplets form on the collector plate separate from PLA fibers. Under appropriate conditions, uniform or beaded liquid crystal PLA fibers were spun. Unfortunately, the resulting mat fibers were randomly oriented on patterned aluminum collector. Despite the difficulties encountered, one very important finding was that the PLA-E7 fiber mat absorbs dye at a significantly faster rate than neat PLA fiber mat. This important result opens up new direction for further investigation, specifically in dichroic dye absorption of LC-polymer fiber mats

2) Effect on the Chain Network of Glassy Polymers from Biaxial Extension

Elizabeth Amory Rowan University Travis Bate Dr. Shi-Qing Wang University of Akron

In a prior study, a molecular model (J. Chem. Phys. 141, 2014) was proposed to explain the yielding and brittle-ductile transitions of glassy polymers. However, the effect of biaxial extension was not explored. Based on our understanding, we expect an increase in ductility when sample is biaxially drawn because twice the number of chains is involved. In this study we began to investigate the effects of biaxial extension on glassy polymers such as polymethyl methacrylate (PMMA), bisphenol-A polycarbonate (PC), and polylactic acid (PLA). The effect of temperature was considered. For temperatures greater than the glass transition temperature Tg we used a custom apparatus that pulls a sample from four sides simultaneously. For temperatures less than Tg we used a customer-made pump system to expand the sample using pressurized water. Using the pump, both PC at ambient and PMMA at 70 ℃ show ductile behavior and fail at λ = 1.47 and 1.35, respectively. The effect of pre-melt stretching is currently under investigation.

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3) Synthesis and characterization of coacervate forming thermoresponsive polyesters for Doxorubicin encapsulation

Yuliana Ospina Yepes Universidad de Antioquia, Colombia Mangaldeep Kundu, Dr. Abraham Joy The University of Akron, Ohio

Encapsulation of chemotherapy drugs, like Doxorubicin (Dox), is a common strategy to reduce toxicity and increase the biological activity against tumor cells[1]. Coacervate-forming thermoresponsive polyesters (TR-PEs) provide a smart method for drug encapsulation simply by changing temperature of the polymer-drug mixture above the lower critical solution temperature (LCST)[2]. In this work, Dox was encapsulated inside degradable TR-PEs containing amino acid mimicking pendant groups.

The high molecular weight (65-80 kDa) TR-PEs were synthesized by carbodiimide-mediated polymerization. NMR and GPC techniques were used to characterize the copolymers. Also, UV-vis spectroscopy was used for the cloud point temperature (Tcp) measurements (14-29 °C) and to monitor polymer degradation qualitatively. Fluorescence microscopy was used to probe the encapsulation of Dox. The successful encapsulation and release of Dox was monitored by UV-vis spectroscopy. There is a burst release for the initial hours because of the diffusion phenomena. By varying the pendant functional groups, it is possible to increase the efficiency of encapsulation. This study demonstrates that TR-PEs can be exploited as an easier method for drug encapsulation in cancer therapy. [1] Park, J.; et al., Nanomedicine, 2009, 5(4):410–418. [2]

Cruz, M. A.; et al., Macroletters, 2018 (7):477-481.

4) Impact of Degree of Hydrophobicity on Hydrogen Bonding Percolation at Water-Polystyrene Interface

Ruth Eckman Grove City College Dr. Mesfin Tsige University of Akron Selemon Bekele University of Akron

In previous simulations by Bekele and Tsige on the properties of interfacial water molecules in contact with polystyrene surfaces of varying polarity [J. Phys. Chem., 122, 9015-9020 (2018)], a marked change in the rates of interfacial hydrogen bond relaxation times and diffusion of interfacial water molecules was observed at a polarity of about 0.06 NO / Å2, which the authors suggested to be the hydrophobic/hydrophilic transition point. In this work, we seek to discover a microscopic explanation for this change in particular and the hydrophobic/hydrophilic transition in general by analyzing interfacial hydrogen bond networks at various degrees of polystyrene surface polarity. As in the original work, geometric criteria based on atomic position are used to determine the presence of hydrogen bonds, and only bonds between water molecules within 3.75 Å of the polymer surface are considered. A modified version of the extended Hoshen-Kopelman algorithm for non-lattice environments developed by Al-Futaisi and Patzek with updates from Metzger, Irawan, and Tsotsas is used to calculate hydrogen bond cluster size at various degrees of surface polarity. Analysis of hydrogen bonds between substrate oxygen and interfacial water molecules indicates a slight change in the rate of cluster quantity growth at approximately 0.04 NO / Å2, shortly before the 0.06 NO / Å2 point at which the bond relaxation time and interfacial diffusion rate changes were observed in Bekele and Tsige’s work. In the future, we hope to further elucidate the implications of these findings with more exhaustive computational and geometric analysis and to explore the hydrophobic/hydrophilic transition in similar systems with different substrates.

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5) Investigation of Clutch Performance for Two-Speed Rotorcraft Transmissions Tristan LaCombe Princeton UniversityMark Valco CCDC US Army Research Laboratory

Future rotorcraft architectures (such as compound helicopters and tiltrotors) can utilize two-speed transmissions to improve efficiency and increase range, payload, and endurance by enabling alteration of rotor-speed between 100% in hover mode and 50% in cruise mode through transmission gear ratio changes. This research examines the performance of three clutch configuration concepts in an experimental two-speed transmission. Data analysis is facilitated through a MATLAB script designed to process the experimental raw data and produce plots of relevant speed-shift parameters. The analysis indicates that transient torque loads and shift duration are strong functions of power level and operating speed, and a key to achieving smooth shift behavior is in the control of clutch engagement. When mounted on the output shaft, the design that uses centrifugal force of oil on a piston to actuate the clutch provides favorable stability characteristics during clutch engagement and produces the most repeatable data of the three clutch configurations. A dry clutch design is preferred over a wet clutch design due to greater coefficient of friction, longer life and lighter weight. A clutch design that combines the above features is recommended for further research and development.

6) Surface Modification of Cellulose Nanocrystals

Ifeyinwa Okafor Miami University Dr. Diana Gonçalves Schmidt Kent State University Dr. Torsten Hegmann Kent State University

Cellulose nanocrystals (CNCs) are emerging renewable, rod-shaped nanoparticles capable of forming a lyotropic chiral nematic liquid crystal phase when suspended in water. The helical pitch and the birefringence increase with the concentration of CNCs in water (Fig.1). The purpose of this study is to observe the behavior of CNCs after surface modification. Here, CNCs were functionalized with a maleimide group followed by the preparation of cyanobiphenyls for a final Michael addition between the maleimide-functionalized CNCs and cyanobiphenyl thiols. By such functionalizing, originally hydrophilic CNCs are now hydrophobic and can serve as unique new chiral additives to study chirality transfer in a variety of other LC phases.

Fig. 1. Birefringence of 2.5 wt.% CNCs in H2O (left) and SEM image showing N*-LC pseudo-layers (right).

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7) Flexoelectric properties of polymer electrolyte membranes based on PEGDA-co-PEGMEA network and Magnesium bis(trifluoromethanesulfonimide)

Khoa Tran St. Mary’s University Hamad Albehaijan, Thein Kyu The University of Akron

Solid-state polymer electrolyte membranes (PEM) were originally developed for solid-state Li-ion battery. According to our previous study, these PEMs possess flexoelectric properties, that is, the generation of electrical energy from mechanical deformation. Membranes fabricated from poly (ethylene glycol) diacrylate (PEGDA) are of particular interest because of their simple fabrication. Here, we confirmed the flexoelectric effect of the studied PEM by showing that current and voltage magnitudes are directly proportional to the amplitude of the mechanical deformation. Composition (PEGDA:PEGMEA)/Mg(TFSI)2 80/20 shows the highest ionic conductivity at room temperature(~2.56 μS/m). However, the composition (PEGDA:PEGMEA)/Mg(TFSI)2 70/30 presents the highest flexoelectric performance (flexoelectric coefficient, μ ~ 502 μC/m). A plausible explanation is that the magnitude of the strain gradient also plays an important role in flexoelectricity. The higher rigidity of sample (PEGDA:PEGMEA)/Mg(TFSI)2 70/30 induces a higher strain gradient upon deformation. Additionally, the introduction of dangling PEGMEA side-chains to PEGDA network is proven to be an effective way to improve ionic conductivity and flexoelectric performance.

8) Using Stimuli-Responsive Polymers to Passively Collect/Expel Water Vapor

Allison Reardon Hanover College Dr. Hunter King The University of Akron Aida Shahrokhian The University of Akron

Around the world, freshwater scarcity is becoming a more renown problem. Water vapor can be turned into a source of freshwater by utilizing smart polymers for water vapor capture and release. Poly(N-isopropylacrylamide) (PNIPAM) is one of these smart polymers that is responsive to temperature. When electrospun, the PNIPAM fibers are fibrous in structure, thus allowing for a high amount of surface area for water vapor collection and expulsion. At temperatures below its lower critical solution temperature (LCST), which is around 32°C, PNIPAM exhibits hydrophilic properties and can collect water vapor whereas at temperatures above its LCST it exhibits hydrophobic properties and expels it. In this study, there are four main objectives. The first objective is to characterize the fibers using the scanning electron microscope (SEM) for size and uniformity, thermogravimetric analysis (TGA) for degradation temperature which is around 400°C, and then differential scanning calorimetry (DSC) for glass transition temperature (Tg). The second objective is to thermally crosslink the PNIPAM chains by finding an optimum temperature that is not much higher than its melting point so that the fibers keep their fibrous structure instead of turning into fiber melts, which will allow them to retain a higher surface area. This was investigated using Fourier transform infrared spectrometry (FT-IR) and rheometry. The rheology results show that the gelation temperature of PNIPAM is about 155°C. However, isothermal crosslinking of the polymer for longer period at lower temperatures (120°C) was confirmed using FT-IR. The third objective is to determine how well the fibers collect and expel water vapor in an environmental chamber with controlled relative humidity and temperature for which calibration curves were acquired.

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9) Polymer-salt Interactions Using Dynamic Light Scattering Mansi Peesapati The University of Illinois at Chicago Susan Kozawa Gary Wnek Case Western Reserve University

To perform even the simplest of activities - drinking water, riding a bike, breathing - our nervous system must carry out a series of perfectly timed commands. It is able to deliver this due to the complex network of neurons that covers the entirety of the human body. This paper aims to study the structural changes happening during neural stimulation through minute macromolecular modeling. This perspective is introduced through observing polymer-salt interactions using Dynamic Light Scattering (DLS). These interactions are of particular interest because they can be used to model the same interactions happening in neurons at their different states. The synthetic polymer, polyacrylic acid is used for this model. DLS is the chosen method of observation as it provides a key measurement of interaction - hydrodynamic diameter. This allows us to observe the size and shape of the polymer and how it changes with fluctuations in salt concentration and ionic strength. It is observed that increasing the ionic strength of monovalent salt solutions causes a decrease in the polymer’s diameter. This is due to the Debye Screening Effect, where the charges on the polymer are shielded by counter-ions in solution, allowing the polymer to aggregate. This effect is seen even more dramatically in divalent salt solutions. The flocculation concentration of divalent counterions is, on average, 100 times smaller than that of monovalent counterions. This leads to shielding and rapid coiling of the polymer at substantially lower ionic strengths than that of monovalent salts. In the future, these observations can allow us to explore further factors for certain polymer manipulation, and understand how these structural changes may be processed in the human nervous system similarly.

10) Enhancing Performance of Lead-Halide Perovskite Solar Cells by Minimizing Energy Losses

Adam Chan Grove School of Engineering at the City College of New York Tao Zhu The University of Akron Dr. Xiong Gong The University of Akron

Researchers have been focused on perovskite solar cells (PSCs) as an alternative to silicon solar cells due to relative cost effectiveness and the drastic rise in photoconversion efficiency in perovskite solar cells. Efficiency has increased from 3.8% to 23.7% since the discovery of perovskite solar cells in 2009[1]. However, PSCs come with drawbacks such as instability and low absorption spectrum. Thus, we want to optimize the solar cell device structure so that it will minimize energy losses. Perovskite materials exist as hybrid materials with the general formula ABX3, where A is methylammonium or formamidium (both organic ions), B being lead or tin ions, X being halide ions[2]. When using lead halide PSCs, absorption spectrum is 800 nm. However, lead-tin blended PSCs have an absorption spectrum of 1040 nm which is correlated to a decrease in bandgap[3]. By introducing n-type conjugated polymer NDI-DPP, it can fulfill three roles (1) low bandgap to broaden absorption spectrum[4], (2) balance hole and electron transfer mobility[4] and (3) potentially forming hydrogen bonds with perovskite ions and its own strong withdrawing groups, potentially hindering ion migration[5]. For future work, we aim to work with lead/tin blended perovskite solutions and NDI-DPP to further enhance the efficiency of perovskite solar cell devices in addition to minimizing energy losses.

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11) Achieving Flat Gold Surfaces for the Organization of Organic Molecules

Jacob Martin Cleveland State University Dr. Jessica E. Bickel Cleveland State University

Organic electronics are interesting for use in devices including solar cells, light emitting diodes, and flexible electronic devices. However, they suffer in competition to their inorganic counterparts due to their lower conductivity. It has been shown that crystallizing organic semiconductors can increase their conductivities. One possible method to crystallize organic molecules is self-assembly driven by the topography and chemistry of an atomic surface reconstruction (a repeating pattern on a crystal surface). This work examines the use of the Au(111) surface, which has a herring bone reconstruction. However, the first step to using such a surface for self-assembly is developing a method to create atomically smooth Au(111) surfaces. One common method to smoothen surfaces is annealing, which allows atoms to rearrange into a lower energy state. This work examines annealing thin films of gold based off the work of Maver et al[1]. We use a propane torch to heat the sample to 710±10°C for two minutes, then lower the torch to anneal at 410±10°C for an additional three minutes. This annealing process yields larger and flatter terraces in comparison to the unannealed material. For the unannealed gold, there were mounds that had no flat areas and had a max depth of 7.6 nm. The annealed Au(111) had flat terraces ranging in size from 13-30 nm and had step heights in the order of .235 nm, which matches the interplanar spacing for Au(111). In the future we will optimize to achieve large terraces by adjusting the temperatures and times used throughout the annealing process.

[1] Maver, Uroš, et al. “Preparation of Atomically Flat Gold Substrates for AFM Measurements.” Acta Chimica Slovenica (2012).

12) Investigation of RNA Chaperone Activity of RsmC and its Change after a Lethal Mutation

Tyler Galbraith University of Texas at Dallas Keshav GC Dr. Sanjaya Abeysirigunawardena Kent State University

Ribosomal biogenesis depends on many factors and steps like rRNA folding, rProtein assembly, and rRNA nucleotide modifications to occurs co-transcriptionally. Specifically, rRNA modifications play a large role in the final folded conformation of the rRNA. Ribosomal RNA small subunit methyltransferase C, RsmC, is a protein that is responsible for the methylation of G1207 as well as some chaperonic activities during ribosomal biogenesis. G1207 has been found to be an important nucleotide because a transversion mutation to a cytidine nucleotide at position 1207 results in a dominantly lethal phenotype. Our group has studied RsmC and its effects on its target region. Five RNA constructs were used to gain information on RsmC’s interaction and effect on duplex formation as well as potential reasons for the G/C mutation lethality. The Circular Dichroism spectroscopy data shows that the G/C mutant is the most stable of the five constructs examined. It was also discovered that the wildtype strand and G/C construct may exist in equilibrium between two secondary conformations. Furthermore, EMSA trials showed that RsmC has a different affinity for the G/C mutant construct when compared to the wildtype strand. Two duplex bands were also able to be separated within the gel which represent both the linear duplex as well as the hairpin looped duplex that the G/C strand can form. Further gels were run to compare the F3 strand with the G/C construct. After analysis, the G/C construct shows the lowest fraction bound values. Lastly, kinetic EMSA gels were run and the resulting data is being used to gather rate constants through curve-fitting models.

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13) Multi-layered Polymer Films S. Scanlon Case Western Reserve University

Multi-layered polymer films offer a wide range of benefits over single polymers. By combining various polymers in distinct layers, a multi-layered film takes advantage of the properties of each polymer. In this work, a mold was created to produce prototype multi-layered bottles through the blow molding process to secure future funding from industry and different polymers were tested for use in the multi-layer blow molding process. The polymer testing yielded shear viscosity, extensional viscosity, activation energy, and a relaxation spectrum for each polymer.

14) Structural Characterization of Oligonuclear Complexes Containing Schiff Base Ligands

Tyler Knisley Stark State College Dr. Scott Bunge Kent State University

The reactions of Schiff base ligands (H3L and H4L) with Ln(NO3)3.xH2O (Ln = Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb), triethylamine (TEA), and trimethylacetic acid (TMAA) results in the formation of families of oligonuclear 4f complexes. This 10-week project entailed the structural characterization of these families of novel lanthanide clusters. 24 4f complexes were determined utilizing single crystal X-ray diffraction and are reported herein.

15) Conformational study of the 1,2-difluoroethane-water complex via microwave spectroscopy Dylan Valente University of Scranton Dinesh Marasinghe Dr. Michael Tubergen Kent State University

Chemists often employ fluorine to tailor the properties of molecules to complete specific tasks, such as when designing new medications. With its small size and high electronegativity, fluorine allows chemists to manipulate the basicity/acidity, polarity, and other characteristics of the molecule. Orango-fluorine compounds are known to form weak hydrogen bonds, but the strength of these bonds are not well studied. This investigation was conducted to examine the conformation of the 1,2-difluoroethane – water complex. 1,2-difluroethane is well studied due to its preference for the gauche conformation, which is believed to be stabilized by hyperconjugation. Investigating the effects of hydrogen – fluorine bonding on the conformation of 1,2-difluoroethane will offer more insight into the strength of these interactions. Computational studies along with Fourier transform microwave spectroscopy was employed. Ab initio calculations suggest that the most stable conformer of the complex corresponds to fluorine accepting a single hydrogen bond from water.

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16) Formation of Epoxy-based Reactive Coordination Polymers with Transition Metal Ions

Robert Walker The University of Mount Union Dr. Ruel McKenzie The University of Akron Sainath Jadav The University of Akron

Coordination polymers are formed from the stereoregular complexation of metal cations with organic ligands. The high surface area and porosity of coordination polymers are attractive for applications in gas storage, separation, and catalysis1. Previously, a multi-ligand and reactive coordination polymer was synthesized by combining the ionic liquid (IL), 1-ethyl-3-methylimidazolium dicyanamide (EMIM DCA), with an epoxy resin and sodium ions. In this work, attempts are made to synthesize a transition metal-based reactive coordination polymer using the same ionic liquid and epoxy resin system. Transition metals are known for forming stable complexes and may contribute to the structural integrity, service ln and functionality of a coordination polymer. For example, transition metals are conductive and are used as catalysts. The introduction of transition metals in the structure of epoxy-based coordination polymers broadens industrial applications of this technology, as well as contributes to the understanding of the coordination polymers in the research community. The transition metal ions in this study are nickel and cobalt. Both nickel dicyanamide and cobalt dicyanamide were synthesized through a metathesis reaction to limit the introduction of exogeneous anions into the system. The synthesized salts had low aqueous solubility limit. Thus far, synthesizing transition metal-based reactive coordination polymer using the proposed ligands has proved challenging with limited success. However, transition metals were successfully introduced into the alkali-earth metal system (Na ion) to produce a dual metal containing system. The cobalt system in particular, underwent many unique color changes during processing as a result of the changes in its hydration state. The synthesized coordination polymers are birefringent and were characterized using polarized optical microscopy.

17) Modeling Active Liquid Crystals in Confinement Corahgan Whipple Kent State University Dr. Robin Selinger Kent State University

Simulations of filamentous active nematic liquid crystals show that dynamic pattern formation is controlled by confinement and by filament density, length, and flexibility.

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18) Optimization of Hydroxypropyl Cellulose (HPC) Microgel Imaging and Characterization Using Scanning Electron Microscopy (SEM)

Samantha Tietjen Cleveland State University Dr. Kiril A Streletzky Cleveland State University Dr. Petru S Fodor Cleveland State University

Microgels are polymer-based spherical nanoparticles suspended in water that exhibit a volume phase transition at a particular temperature. The standard, noninvasive method for characterizing microgels is with dynamic light scattering (DLS), which measures the collective diffusion of microgels exhibiting Brownian motion in a sample volume. While DLS provides reliable estimates for particle structure and dynamics, more direct methods of imaging are useful for studying polydisperse samples. Traditionally, scanning electron microscopy (SEM), uses an electron beam under high vacuum to characterize individual particles of dried samples. The dry particle imaging suffers from two main drawbacks in the case of microgels: the dehydrated particles shrank from their expected size by a factor of three, and dynamics are not observable due to particle immobilization. To counter these problems, this project explored wet particle imaging in an ionic liquid stable under high vaccum. Particles were suspended in a thin ionic liquid film on a copper grid and still images/movies were recorded to analyze the sample for both size distribution and dynamics. The average SEM sizes of the two samples tested generally agreed with the sizes obtained by DLS for the same particles both in ionic liquid and water at room temperature. Variation was observed in individual particle size, but the average SEM size for both samples were close to their DLS sizes. Initial attempts at diffusion analysis using SEM particle tracking yielded mixed results as it requires tracing of many particles and further optimization.

19) Potassium citrate-assisted synthesis of tannin-derived nitrogen-doped porous carbon spheres for carbon dioxide adsorption Elizabeth Phinney Rollins College Jenjira Phuriragpitikhon Dr. Mietek Jaroniec Kent State University

Nitrogen-doped micro-mesoporous carbon spheres (N-MMCS) were successfully synthesized using condensed tannins in place of synthetic phenolic compounds as carbon precursors. Such N-MMCS were fabricated by using a modified one-pot Stöber synthesis in the presence of Pluronic F127 and potassium citrate, which act as a structure-directing agent and in-situ chemical activating agent, respectively. To further demonstrate a green synthesis route of this work, in addition to tannins used instead of phenolic resin precursors, L-lysine was used as the base catalyst and nitrogen source in lieu of toxic ammonia. The development of the porosity in N-MMCS was achieved by varying the amount of potassium citrate added to the reaction. The resulting potassium citrate-containing nitrogen polymer spheres were simultaneously carbonized and activated at 800 °C. The proposed strategy allowed for enhancing porosity, especially mesoporosity, with the retention of spherical morphology and mesoporous structure of the resulting N-MMCS. Additionally, elemental analysis showed that all samples were successfully doped with nitrogen. High CO2 uptakes of 4.29 mmol/g at 0 ˚C and 3.27 mmol/g at 25 ˚C were achieved at 1 bar pressure for an activated sample with 0.4 g of potassium citrate (N-MMCS-4K) having the surface area of 729 m2/g, ultramicropore volume of 0.23 cm3/g, micropore volume of 0.26 cm3/g, and mesopore volume of 0.29 cm3/g.

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20) Synthesis of Kaurenoic Acid Emily Williamson Kent State University

Dr. Jeffrey Mighion Kent State University

Natural product synthesis has become a vitally important field of organic chemistry over the last few years. Furthermore, with increasing demand for antimicrobial and pain-relief medications, the need for synthetic strategies for new drug design has risen to a new high. To accomplish this goal, we designed an innovative synthesis of kaurenoic acid from stevioside, an abundant and inexpensive alternative sweetener; kaurenoic acid can be used as a parent molecule for the synthesis of diterpene derivatives. These biologically active diterpenes have been shown to possess antibacterial, anti-inflammatory, and pain-relief properties, making them invaluable to medicine. Currently, there is no optimal process to synthesize the molecule kaurenoic acid, so development of a synthetic pathway that is both cheaper and more scalable would allow access to these vital diterpenes. The synthetic pathway developed by our group requires the implementation of nine organic reactions and now provides access to the diterpene derivatives of kaurenoic acid. Future work will focus on improving selectivity to prevent competitive side reactions, optimization to improve overall yield, and removing chromatography steps to aid in scalability of the overall process.

21) Using Depolarized Dynamic Light Scattering to Study Microgel Volume Phase Transition Andrew Scherer Cleveland State University Dr. Kiril A. Streletzky Cleveland State University

Microgels, for the purpose of this study, are crosslinked polymer (hydroxypropyl cellulose, HPC) particles suspended in water. These microgels exhibit a thermally reversible volume phase transition as a result of the amphiphilic properties of the parent polymer. Specifically, the microgels deswell above a volume phase transition temperature, Tv. Microgel dynamics below and above Tv have been studied extensively by dynamic light scattering (DLS) before. Here, HPC microgel shape fluctuations and/or geometric anisotropy is investigated through the technique of depolarized dynamic light scattering (DDLS). The technique has previously been used in our lab to examine geometric anisotropies in nanorods, nanorice, nanodiscs and other shapes. It has also been used in the literature to study shape fluctuations in microgels that have a hard, polystyrene core and a soft, polymer shell (“core-shell microgels). The current study shows that HPC microgels, consisting only of polymer with no built-in hard core, do exhibit a DDLS signal distinct from a polarized signal, both below and above the transition. The origin of this signal, which can arise from either geometric anisotropy or shape fluctuations, is being examined in detail for a series of microgels of different densities crosslinked at various synthesis temperatures. Preliminary results suggest that our samples undergo shape fluctuations, but further experiments are needed to confirm this.

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22) Development of neural/glial co-culture for remyelination studies in neurodegenerative disease Lauren Syrup University of Alaska Anchorage Brad Popovich Dr. Soumitra Basu Kent State University

Multiple Sclerosis (M.S.) is a neurodegenerative disease caused by an immune response that triggers inflammation, killing myelin and oligodendrocytes in the brain. This can lead to lack of motor function, among other complications. Current treatments for M.S. involve stopping the immune response and slowing the progression of the disease in doing so. However, there are no current treatments for remyelinating the axons and reversing the progression of M.S. Co-cultures of oligodendrocytes and neurons are often used in studies for treatments of M.S.; current studies using co-cultures are expensive, difficult to use, or lack proper differentiation. The first goal of this study is to develop a co-culture of oligodendrocytes and neurons, using cell lines of MO3.13 and SH-SY5Y, capable of differentiating without the help of chemicals such as retinoic acid (RA) and PMA, which is a current practice. The second goal is to use the co-culture in the study of increasing myelin production using AuNP to deliver either N-acetylaspartate (NAA) or acetate to the oligodendrocytes. NAA is required to make myelin, getting cleaved by ASPA into acetate, a raw material used to produce the myelin sheaths. Our findings thus far indicate an increase in myelination in the AuNP NAA and acetate delivery, as well as increased differentiation in the co-cultures that are not treated with PMA or RA. Further research is being performed to determine quantitatively the amount of myelin that is produced as a result of the AuNP delivery system.

23) A Silver-Catalyzed Synthesis of Cyclobutenones: Improvements in Hunsdiecker Decarboxylation Erik B. Feeley Kent State University Dr. Christopher J. Fenk Kent State University

The synthesis of cyclobutenones—a useful intermediate in a wide variety of organic reactions—has to date required the use of stoichiometric or greater quantities of toxic heavy metals in a key synthetic step, i.e. a Hunsdiecker decarboxylation-bromination. Recent literature indicates that Hunsdiecker reactions may be performed catalytically using low molar percentages of a chelated silver triflate catalyst on both aryl and long-chain aliphatic carboxylic acids. This research was intended to investigate the feasibility of these catalytic pathways with regards to small cyclic molecules such as cyclobutenones and investigate the use of the described silver catalyst in the preparation of cyclobutenone from 3-oxocarboxylic acid, a commercially available reagent. It was successfully demonstrated that catalytic synthesis of the Hunsdiecker product was possible, albeit at lower yields (35%) than existing methods. However, optimization of reaction conditions is likely to improve yields considerably. In addition to the success of the Hunsdiecker reaction, this research resulted in significant improvement in the synthesis of the silver triflate catalyst over existing methods.

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24) Synthesis of Gold Nanoparticles Using Microfluidic Mixers

Benjamin Bosela The University of Toledo Alexa Roberts Cleveland State University Dr. Chandra Kothapalli and Dr. Petru Fodor Cleveland State University

Microfluidic devices can be used to perform multiple chemical reactions on a small scale. Some benefits of microfluidic reactions rather than batch reactions include greater portability, more accurate data, quicker reactions, precise verification of temperature, and more cost-effective experiments. Microfluidic mixers can be used to synthesize gold nanoparticles by mixing gold chloride and sodium citrate. Previously, the optimal set of mixing conditions was concluded for a reverse staggered-herringbone mixer. Currently, four different mixers were put in place and tested using the same conditions for each mixer. After collecting samples from the outlet tube of the mixers, sample preparation was completed and the samples were analyzed using SEM. Particles sizes were measured and quantified during the imaging. Particle size distributions were constructed and results for each mixer were compared to comprehend the effectiveness and ability of the different devices. Future work will entail testing different flow rates, temperatures, and pH levels to see how they effect particle sizes in these four different mixers.

25) Characterizing the Relationship of Temperature, Ethanol Concentration, and Turbidity of Absinthe.

Anna Ellis Cleveland State University Dr. Andrew Resnick Cleveland State University Dr. Jessica Bickel Cleveland State University

Oil flavored alcohols are traditionally served by mixing them with cold water to form a louche: a microemulsion that turns the drink opaque. This is because of how the alcohol interacts with the water, which it dissolves, and the oil, which it disperses. Thus, when there is sufficient water the oil phase precipitates, forming a microemulsion (the louche). This means that a characterization of the louche depends on the concentration of water, alcohol and oil. The louche of absinthe has not been as well characterized as other oil flavored alcohols such as Limoncello or Ouzo. This study aims to investigate the emergence of the louche phase in Absinthe by measuring the optical transmittance of Absinthe as a function of both: (1) the concentration of ethanol and (2) the temperature, which can be separately varied. The laser transmission was measured through a temperature-controlled sample of absinthe. The change in transmission was recorded as water was added to the sample, revealing an inverse relationship between temperature and ethanol concentration at which louche forms. This unique project provides a light-hearted introduction to the fields of critical phenomena and materials science.

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26) Characterization of Irradiated and Non-Irradiated Multiply Alkylated Cyclopentane (MAC) Grease Adam DeLong University of California, Merced Samuel A. Howard, Christopher DellaCorte Richard Manco Christopher DellaCorte NASA Glenn Research Center

In the upcoming Europa mission NASA wants to send a probe into Jupiter’s orbit with the intent of studying Europa, one of Jupiter’s moons, by taking pictures of it when they pass each other. The probe taking pictures will be passing through belts of radiation and will be exposed to radiation with each orbit. A concern associated with this is if this radiation will degrade the grease commonly used to lubricate the systems found in space craft. To ascertain whether the effects of radiation makes this lubricant obsolete a spiral orbit tribometer (SOT) was used to conduct friction and lifetime tests. For these tests, a bearing ball with a light amount (25 ~ 30ug) of irradiated and non-irradiated grease was applied to the ball and tested. The conclusion was made that the irradiated grease did not produce a noticeable difference in performance.

27) Utilizing Polymers to Extract Heavy Metals from Water Kaylynn Cooper Central State University Dr. Suzanne Seleem Central State University Dr. Hossein Ghassemi Case Western Reserve University

Water is an essential nutrient to keep good health and accurate body function. When water quality is compromised, its usage puts users, especially children, at high risk of developing severe health complications. The environment also suffers when the quality of water is subpar. Due to water pollution and contamination, the scarcity of safe water is increasing globally. The synthesized polymer, PVAm, showed good adsorption capabilities for heavy metal removal in aqueous solutions. Lignin, a natural resin that has a three-dimensional polymer structure, was also found to be a useful adsorbent material for removal of heavy metals from water. Conjoining both PVAm and lignin created a hydrogel network system with high surface area capable of adsorbing heavy metals. PVAm-lignin filters were produced at different concentrations, and utilized to remove Pb2+ ions from water. Trace analysis of Pb2+ ions in the filtered solution was carried out utilizing atomic absorption spectroscopy. It is expected that the above combined filtration method will decrease the initial concentration of lead ions from 1 ppm to 15 ppb or less, which is the accepted EPA levels forPb2+ in drinking water.

28) Design Modifications and Manufacturing of a Bioreactor to Culture Cartilage Zachary Adams, Georgia Institute of Technology Harihara Baskaran Case Western Reserve University High quality cartilage tissues are essential for improved medical treatment of damages to joints that cannot be otherwise repaired. Due to requirements for nutrients and clean growing conditions, cartilage cells grow best in a bioreactor. To better understand the growth and physical properties of these tissues, the cells are imaged continuously during the growth process. The bioreactor is designed specifically to allow for this imaging, allowing to nondestructively evaluate the growing cartilage cells. In this project, a bioreactor used in a previous experiment was modified to support a new signaling type for the cartilage cells. The new bioreactor works as designed and will likely work well for growing actual cartilage cells.

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29) Investigating the structure of atmospheric plasma polymerized thin films Cagatay Yilmazoglu University of Akron Brenna Rossi University of Akron Mark D. Foster University of Akron

Plasma Enhanced Chemical Vapor Deposition (PECVD) in vacuum has been used to deposit uniform thin films from vaporized monomer without releasing volatile organic solvents into the environment. These films tend to be highly crosslinked, and, when deposited from appropriate monomers, have been shown to slow corrosion when applied to metals. However, the inconvenience and expense of depositing in a vacuum chamber has hindered the application of this technique by industry. Therefore, attention has turned toward atmospheric plasma polymerization (APP) methods, which are performed under ambient conditions. While several groups have demonstrated that PECVD in vacuum can deposit films that are laterally very uniform, and some have studied such films with techniques such as X-ray reflectivity (XRR), there are no published reports of successful XRR characterization of APP-films. In order to deposit films uniform enough to do XRR, the deposition conditions were optimized. XRR data from a film of sufficient lateral thickness uniformity can be analyzed to obtain information on the film surface roughness, roughness of interface with the substrate, and variation in structure with depth with a resolution of 1-2 nm. Characterizing film at this level makes it possible to both compare the structures of APP films with the structure of films made using vacuum deposition and to further optimize APP film deposition to provide uniform corrosion protection.

30) Characterizing Gegenees, a Thermoreversible ELP-based Star Polymer

Mario Alberto Cleveland State University

Dr. Kiril Streletzky and Dr. Nolan Holland Cleveland State University

Elastin-like polypeptides (ELP) are biopolymers that form thermoreversible aggregates above a certain transition temperature (Tt). It is important to note that this temperature is not a static property of the system, it changes based on the concentration of ELP, the salt concentration and the pH of the solution. An EL P based star polymer has been formed by bonding a structural protein from a virus to one end of the ELP chain. This structural protein, named foldon, trimerizes, causing the structure to assume the conformation of a star polymer. This project investigates the behavior of a six-armed star polymer (informally known as Gegenees) with decorin fragments placed at the end of the polymer chain opposite to foldon. These polymers were studied with two different ELP chain lengths: n=10 (G10) and n=19 (G19). Changing the conformation of ELP from a straight chain to a many-armed star polymer allows for increasing the number of functional groups that can be attached to ELP particles. These particles have many applications in tissue engineering, targeted drug delivery, and cancer therapy.

These particles were characterized by determining the Transition temperature at a variety of ELP concentrations. These transition temperatures were fit to pre-existing models for ELP particles to compare how placing the ELP into a star polymer influences its characteristics. The particles diameter was measured by dynamic light scattering (DLS). The solutions tended to be at the limit of opaqueness for DLS. Further optimization of this system is required for more effective DLS analysis.

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31) Microfluidic Synthesis and Characterization of Lead Iodide Perovskite Nanoplatelets Quinton Wright University of Tennessee, Knoxville Dr. Chandra Kothapalli Cleveland State University Dr. Geyou Ao Cleveland State University Dr. Petru Fodor Cleveland State University

Perovskite nanoplatelets (PNPs) are two-dimensional semiconducting nanomaterials exhibiting bright photoluminescence and spectrally narrow absorption and emission. Until recently, PNPs have been synthesized using one of several batch synthesis methods. The current work demonstrates a continuous synthesis method utilizing microfluidic technology. In this research, lead iodide PNPs of varying thickness were synthesized via non-solvent crystallization using both microfluidic platform and batch synthesis routes. The resulting nanoplatelets are characterized by spectrophotometry and scanning electron microscopy. Results demonstrate that nanoplatelets could be synthesized in a reverse staggered herringbone microfluidic mixer, and such nanoplatelets exhibit improved properties compared to their counterparts from batch synthesis. PNPs (n=1) synthesized using microfluidics exhibit spectrally narrower absorption and emission than their batch synthesis counterparts, and PNPs (n=2) without excess ligands could be obtained at a significantly higher purity when synthesized with microfluidics. Future work would seek to optimize the microfluidic synthesis of such PNPs.

32) Synthesis of Hyperbranched Polymethacrylates Using an Inimer Approach

Amanda Dershem Siena Heights University Dr. Coleen Pugh University of Akron Gavan Lienhart, Chenying Zhao University of Akron

Hyperbranched polymers have a variety of unique characteristics that make them suitable in applications for which linear polymers are insufficient. Among these unique properties are low viscosity, high solubility, and the potential to maximize the number of available functional groups in the molecule. In this study, hyperbranched polymethacrylates were synthesized using ATRP and then characterized. Inimers—precursors to polymers that have an initiating site as well as the monomer unit—were synthesized as the starting material for the ATRP reactions. Due to their dual nature, inimers are excellent for synthesizing hyperbranched polymers, as they have multiple sites where chain growth can take place. After the specific reactions were optimized, NMR, DSC, and GPC were used to characterize the inimers and subsequent polymers produced. Of particular focus in this study was the poly(butyl methacrylate) molecule, which verified the versatility of the procedure as the second successful polymethacrylate synthesis.

Figure 3—Reaction schematic for hyperbranched polymethacrylate synthesis using an inimer approach

NH2

OHOH

O

NH2

O

OH

D, L-Alanine Methyl Serine

BrO

OOH

OMethacrylic Anhydride

p-TSA

Pre-InimerBr

OHOH

O

KBr, HBr, NaNO2

Methyl Bromohydrin

1. PCl5

BrO

OO

O

R

Inimer

2. Alcohol,

Et3N, THF

H2O

CuSO4, HCHO, K2CO3

H2O

O

OO

O

RCuBr, Ligand

Solvent

HB Polymer

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33) Mesoporous carbon and multi-walled carbon nanotubes for electrochemical applications Alyssa Agler Mount Vernon Nazarene University Mohammad Akter Hossain Dr. Hao Shen Kent State University

There is an increase in the need for efficient energy storage and conversion. In the past conventional capacitors have been used, but these have low energy density. Electrochemical supercapacitors have been gaining interest due to their high energy density, fast ability to charge, longer charge-discharge cycles, and broader temperature operating range. These supercapacitors increase capacitance due to being porous which increases surface area. This allows more charge to accumulate on the electrodes. In this study, a three-electrode system was used. A mixture of either mesoporous carbon or multi-walled carbon nanotubes with carbon black and nafion were applied to nickel foam and glassy carbon. Then a cyclic voltammogram was recorded and capacitance was calculated from this measurement. It was found that nickel foam has more capacitance activity than glassy carbon. Also, multi-walled carbon nanotubes have more capacitance activity than mesoporous carbon when applied to the nickel foam without carbon black or nafion. Future tests can be performed with different carbon samples and different electrode setups that may yield different results.

34) Development of EDTA Crosslinked Beta-Cyclodextrin for Use in Drug-Eluting Cardiovascular Stents Grace Burkhart Valparaiso University, Department of Chemistry Kathleen Young, Horst A. von Recum Case Western Reserve University, Department of Biomedical Engineering Nathan Mu University School

Drug-eluting stents (DES) reduce the occurrence of in-stent restenosis in patients who have a stent placed in cardiac arteries. However, current DES do not have a long enough window of drug release to prevent late in-stent restenosis. Beta-cyclodextrin (BCD), a polymer which is capable of drug elution, has a high biocompatibility, is able to be refilled with drug, and can be polymerized using Ethylenediaminetetraacetic acid (EDTA). The EDTA-BCD polymer particles have shown good attachment on Cobalt Chromium cardiovascular stents by imaging with SEM and analysis with EDS. Drug release studies done on the particles have shown extended drug release, showing that EDTA-BCD polymers have the capability of being a refillable and biocompatible coating for cardiovascular stents that can reduce the occurrence of late in-stent restenosis.

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35) Mechanical Reinforcement of Elastomers with Changes in Filler Network Structure and Silane Coupling Agent

Avery Gould John Carroll University Dillon Presto Mark D. Foster University of Akron

A major challenge in dispersing silica filler in elastomers is the difference in polarity between the silica and rubber, which results in poor reinforcement. Silane coupling agents enhance the interaction between silica filler particles and rubber. We have investigated how (3-mercaptopropyl)trimethoxysilane (S1) and bis-(3-triethoxysilypropyl)-disulfide (S2) affect dispersion and the quality of elastomer reinforcement in elastomeric compounds with styrene butadiene rubber (SBR). We have also analyzed how these silane coupling agents affect the hierarchal structure of the silica filler network from the nanoscale to the microscale with ultra-small-angle X-ray scattering (USAXS). In addition to structural analysis, we have elucidated the dynamics of nanoscale structural rearrangements of the silica particles in these filled rubber systems with X-ray photon correlation spectroscopy (XPCS). We observe that S2-treated silica creates smaller, denser aggregate structures than does S1 silica. XPCS results show that the smaller structures in the S2-treated system are correlated with more rapid structural rearrangements at small oscillatory strain amplitudes (~0.5%). However, there is a crossover in behavior with increase in strain amplitudes. At the largest strain amplitude probed (~24%), the most rapid rearrangements are observed for untreated silica. Thus, the most optimal silane coupling agent depends on the strain amplitudes characteristic of the target application.

36) Nutrient Transport in Hydrogel Scaffolds for Tissue Engineering

Jose Luis Pena Texas A&M University Kaitlyn Mawhinney, Dr. Sadhan Jana University of Akron

Gels are three-dimensional porous interconnected structures that have been increasingly studied for drug delivery systems and implants in tissue engineering. The porosity and pore size of the gel may be tuned using an emulsion as a template to construct macro-voids in a mesoporous network. The purpose of this research is to study nutrient transport in emulsion templated polyurea hydrogels for their application in tissue engineering of lumbar intervertebral discs. The sol consists of Desmodur N3300 in dimethylformamide (DMF) and water which yields urea once gelation occurs. The process is accelerated by using triethylamine as a catalyst (TEA), and n-heptane is used as the dispersed phase. The gels are subjected to solvent exchange from DMF to water with acetone as a bridging solvent to yield water-filled monoliths. Diffusivity of sodium chloride was measured through three different gels: control and emulsion-templated PUA, using 30 and 60 v/v% n-heptane as the dispersed phase. The diffusion coefficients of the gel samples were measured in a controlled environment in a diffusion box at constant pressure, temperature, concentration, and contact surface area. Diffusivity rate appeared to increase with increased porosity. In the most precise measurements, the diffusion coefficient of the 60 v/v% n-heptane templated gel was almost three times greater in magnitude in comparison with the control polyurea, which is attributed to the lower polymer content and large voids created in the gel network.

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37) Explorations in cancer treatment: G-Quadruplex binding kinematics

Matthew Sunthimer Kent State University Sagun Jonchhe, Changpeng Hu Dr. Hanbin Mao Kent State University

The classical depiction of DNA consists of B-DNA: A twisted double helix with Watson-Crick base pairing (ATGC). Advances in genetics, molecular biology, and biophysics have uncovered many species of Non-B DNA structures within mammalian genome such as the G-Quadruplex (GQ), hairpin-loop, cruciform and triplex, each of which demonstrate functional properties such as regulating genetic expression and DNA synthesis etc. Extensive research has uncovered >760,000 GQ hosting sites which are characterized by sequences rich in Guanine. GQs have become the target for many ligands as previous research has demonstrated that strengthening telomeric GQ stability can interfere with constitutive telomerase activity—the necessary enzyme for immortalization of cancer cells. Previously we have performed force-extension assays using single molecule laser tweezers to test monovalent ligands as well as polyvalent linear shaped dimeric and tetrameric telemerstatin derivatives, each of which has demonstrated characteristic binding kinetics to the GQ. Surprisingly, the tetramer has demonstrated much lower binding to the single GQ as compared to the monomer or dimer. Further analysis revealed that the linear topology allowed for intramolecular stacking between the binding domains, sterically hindering the ligand from interaction with the GQ. Here, we have examined a polyvalent hexameric ligand to further investigate the contribution molecular topology has in binding kinetics. We found that the spherical topology of the hexamer was enough to overcome the intramolecular interference which dominated the behavior of the tetramer. Our findings demonstrate the importance of the topological features of ligands and may be of importance in designing more efficient anti-cancer agents targeting these GQs.

38) Evanescent Wave Scattering as A Versatile Technique for Characterizing Anisotropic Particle Dynamics Under Complex Fields Peter Howard Louisiana State University Dr. Christopher Wirth Cleveland State University Jiarui Yan Cleveland State University Colloidal particles are a highly diverse class of materials that can be observed in numerous everyday situations ranging from ventilation systems to food processing. Colloidal particles can also be fabricated to function as models for more complex systems of biological or mechanical interest to study and characterize their behavior in controlled experimental conditions. Our research makes use of Evanescent Wave Scattering via Total Internal Reflection Microscopy as a sensitive technique to measure small fluctuations in the dynamics of two model, anisotropic, “Patchy” and “Janus” colloids with two distinct surface chemistries at 30% and 50% coverage respectively under the influence of an applied AC electric field. Aqueous dispersions of the model colloids were observed in the TIRM setup and allowed to undergo Brownian fluctuations while collecting videos of the light from the incident laser scattered by the particles at conditions with the applied field on and off. Plots of scattering intensity against time were generated to visually compare the influence of the applied field on the overall scattering. Due to the additional factor of distinct surface chemistries we also hypothesize that patch coatings induce additional dynamic effects under the influence of an electric field including exaggerated rotation. To visualize these dynamics, histograms were prepared and compared to the bimodal distributions we anticipate emerging from particles undergoing axial rotation as well as to support our observations of a variety of other dynamic behaviors including propulsion and particle movement both towards and away from the boundary.

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39) Effect of Chemical Structure and Reaction Time on the Swelling Properties of Polyelectrolytes in Various Solvents

Claire Senger University of Minnesota Twin Cities Juan Marin The University of Akron Dr. Kevin Cavicchi The University of Akron

An ion-pair comonomer (IPC) of styrene sulfonate (SS) and trioctyl vinylbenzyl phospohonium (TOP) chloride has recently been shown to form a high glass transition temperature (190C) thermoplastic polyampholyte complex when polymerized (TOP-SS), which is difficult to achieve in non-ionic carbon-carbon backbone polymers through free radical polymerization. In this work, we seek to understand how the polymer will swell when exposed to water and other solvents. Four other similar polymers will also be tested to determine the cause of any swelling in the polymer, each varying in bonding or structure. The TOP-SS polymer has double bonds at both the cation and anion, allowing for cross-linking on both sides. The tested variations include giving the anion or cation a single bond instead of a double bond, the size of the anion, and increasing the amount of charges in the monomer. The IPCs for the polymerizations will be synthesized using nucleophilic substitution and ionic exchange reactions, and the polymers were synthesized via RAFT polymerization for 15, 24, and 48 hours. It was found that the TOP-SS and SS-TOP-TOP-SS, the polymer with more charges, polymerized for 15 hours did not significantly swell in water, but did so in ethanol, both gaining 80 to 100% in mass over six hours. The SS-TOP-TOP-SS polymer not swelling in water indicates that even with more charges, the water can still not break up the network and hydrophobicity is high. The swelling in ethanol indicates that the networks are hydrophobic and are broken down by the ethanol. Further work is being done in the cases of the other three polymers.

40) Analysis of Earthworm Locomotion Characteristics Zoe Moore Case Western Reserve University Victoria McLaughlin Case Western Reserve University

Earthworms are of great inspiration in the creation of a soft robot. They have the ability to move across various types of surfaces, burrow into the ground, and change their shape in many ways to accommodate for different challenges that arise. A robot with worm like characteristics would allow for future applications such as medical procedures, search and rescue missions, pipe inspection and more. This research focuses on the analysis of the locomotion characteristics of the worms. Video data of the earthworms moving across different surfaces was used in determining the maximum and minimum changes in the diameter of the worm during normal gait, the approximate number of segments that is contained in each wave within the worm, and the approximate change in length of each segment of the worm. This data will be heavily considered in the construction of a future earthworm inspired robot.

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41) Multiresponsive Ionic Liquid Crystal Elastomers for Soft Robotic Applications Kristen Campobasso The University of La Verne Chenrung Feng Dr. Antal Jakli Kent State University

This poster investigates pathways to make ionic liquid crystal elastomers (iLCEs) multiresponsive by ultraviolet light and electric field. ILCEs are a new type of liquid crystal elastomer that can be actuated by low electric field (0-3V). By applying an electric field across the iLCE film, the positive and negative ion flow causes asymmetric volume changes on two sides of the film and generates bending deformation. However, the light response of iLCEs has yet to be studied. In this project, we added Azobenzene containing LCs into iLCEs and achieved fast UV light responses even at room temperature. Moreover, we can tune the ionic conductivity of the iLCE film using UV light, and thus, control the electric actuation. This new discovery has potential applications for low power consumption soft robotics and sensors.

42) Structural Elucidation of Polymeric Surfactant Mixture by Hyphenated Multi-Dimensional Mass Spectrometry

Zane Tolbert Walsh University Jason O’Neill, Chrys Wesdemiotis, Ph.D. Akron University Department of Chemistry

A surfactant is a chemical that decreases the surface tension between two liquid phases. They can be found in detergents, skin care products, cleaners, foods, and many other products. Surfactants are composed of hydrophobic and hydrophilic groups, with the ratio of these two controlling the physical properties. To increase performance, surfactants are regularly complex mixtures, containing both natural and synthetic moieties. In addition, because surfactants are often manufactured products, not much more information than the name is given. Due to this, their analysis can prove to be complicated, requiring hyphenated separation techniques. Hence, ultrahigh performance liquid chromatography ion mobility mass spectrometry (UPLC-IM-MS) was used to separate and characterize a commercially available surfactant comprised of a glycerol core, various degrees ethoxylation, and functionalized with fatty acids sourced from coconut oil (Resassol Coe, Res Pharma Industriale). UPLC facilitated separation of the surfactant based on relative polarity and IM facilitated separation based on shape and charge. Due to various compounds having similar polarities and/or shapes, combining the UPLC and IM techniques delivered greater separation and resulted in a much less complex spectra. Within the surfactant mixture, 23 unique distributions were observed and confirmed by accurate mass and tandem mass spectrometry. The degree of ethoxylation ranged from 3-13 with an average of 7 ethylene oxide units. The fatty acid profile was found to be as follows: 35% Lauric (C12), 17% myristic (C14), 13% capric (C10), 11% palmitic (C16), 9% gondoic (C20:1), 8% stearic (C18), 6% oleic (C18:1), 1% caprylic (C8). The observed fatty acid profile is similar to that of the coconut oil profile found in literature and both contain high percentages of lauric. However, stearic and gondoic fatty acids are not typically found in coconut oil. This suggests that the surfactant was not synthesized with solely coconut oil, but rather with a mixture of oils.

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43) Multivariable Stress Chamber for Partial Discharge Measurements Cole Harlow The Ohio State University Andrew Trunek NASA Glenn Research Center

In recent years, there has been a growing interest in the development of high-efficiency, low-carbon emission, electrical aircraft propulsion (EAP). To enable this technology, the development of a low weight power-transmission system is necessary. Current aircraft use low-voltage (<1KV) power-transmission systems which would require prohibitively large power lines to meet the requirements of proposed EAP. This has led to an interest in high-voltage (HV > 1KV) variable frequency AC power systems. These systems avoid large power lines by requiring significantly less current to transfer the same power. Unfortunately, HV power systems are known to suffer from partial discharge (PD) which is a result of high field strengths and imperfections in insulation. Overtime, PD will cause damage and eventual failure of HV insulation. The treatment of PD in terrestrial HV systems is greatly simplified by the lack of insulation size or weight constraints. Because of this many terrestrial methods of mitigating PD cannot be applied on aerial vehicles. The implementation of insulation in airborne HV systems is further complicated by the large environmental variability that aircraft components are subjected to. The decrease in the dielectric breakdown of air at lower pressures (found in higher altitudes) is a well-documented phenomenon known as the Paschen Curve. Additionally, other works have suggested that additional parameters such as temperature, humidity, vibrations, and driving frequency could impact the lifetime of the insulation. For these reasons, this project has aimed to develop a test chamber capable of studying the impacts of the above parameters on the occurrence of partial discharge within the insulation of HV transmission lines. Such a test chamber would allow for the rapid development of the insulation necessary to enable HV variable frequency AC power systems.

44) Investigation of Anomalous Hysteretic Losses in Mouse Tendons

Stephen F. Adasonla Cheyney University of Pennsylvania Dr. Henry C. Astley The University of Akron

Elastic energy storage is widely seen in nature, responsible for allowing the human body to perform activities such as walking, running, and jumping. Tendons are the main site of elastic energy storage in vertebrates. In conjunction with skeletal muscle, tendons assist body movements by ways of energy conservation, power amplification, and power attenuation. The conventional wisdom of low energy loss in tendons states that a <10% of energy is lost when loading and unloading forces on large species. In the last two years, REU students found and confirmed that mouse tendons demonstrate an unusually high rates of hysteretic energy loss during stretch-shorten cycles. This eventually leads to a loss of more than 40% of the energy stored during stretching. This calls into question the validity of using mice when testing the effect of drugs or treatments on tendon properties. This project will re-confirm the previous findings and use new methodology to test for potential confounding effects such as change in osmotic pressure, temperature change, prolonged storage, and comparison to tendons of species (e.g. rabbit, squirrel, etc.). Video footage was recorded of the rabbit tendon samples to examine the uniform movement as loading and unloading forces were applied. Infrared imaging was also used to capture the loss of energy from these tendons in the form of heat. Results from this experiment have confirmed previous conclusions. Achilles tendons of mice, squirrel, rabbit, and chipmunk demonstrated a loss of energy ranging from 27%-33%. This proves that this anomaly is not exclusive to only laboratory mice, but also varying small rodents found in nature.

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45) 3D Printing of Polyimide Aerogels Theresa Nosel University of Connecticut Melica Nikahd Lipscomb University Jessica Cashman NASA Glenn Research Center Stephanie Vivod NASA Glenn Research Center Haiquan Guo Ohio Aerospace Institute Polyimide aerogels are a nanoporous material made by extracting the liquid portion of a wet gel and replacing it with air, while still maintaining the porous solid internal architecture. This results in a material with extremely low densities, low thermal conductivities, high internal surfaces areas, and low dielectric constants. Currently, complex aerogel forms are not possible, since they require molds in order to be shaped. To overcome this challenge, we are attempting to use various additive manufacturing techniques to produce complex architectures. Three different approaches are being studied to accomplish this. One is to print using a viscous wet gel and have the structure solidify at the end of the print, another is to use a mixing tip, where a less viscous gel and the final chemical that causes gelation will be mixed as it is printing, allowing it to gel layer by layer, and the third is to use a UV curable aerogel with a UV light following behind to solidify the gel as it prints. To have these approaches be successful, the printing parameters and the aerogel’s chemical formulation need to be optimized. The more harmonious these two factors can be made, the more defined and complex the resulting structure can be. Preliminary results show that 3D printing polyimide aerogels are a viable option, but further optimization must occur for reliable printing.

46) The Design of 3D-printed Scaffolds for Wound Infections and Inflammation

Walid Abuhashim The University of Akron Yen-Ming Tseng, Chinnapatch Tantisuwanno, and Tanmay Jain The University of Akron Dr. Abraham Joy The University of Akron Treating chronic wounds is challenging due to the multiple parameters that affect the healing of wounds. Chronic wounds cause persistent inflammation and serve as a site for the growth of bacteria and their entry into the circulatory and bodily systems. Patients with chronic wounds may undergo multiple rounds of bandage changes, leading to aggravation of the wound and patient discomfort1. We are addressing some of the drawbacks of current chronic wound treatment by developing polymeric 3D printed scaffolds embedded with therapeutics that can maintain a sustainable release over several days. These scaffolds will decrease the number of changes in bandages. In our study, we used Diclofenac Sodium, a non- steroidal anti-inflammatory drug, and Ciprofloxacin HCl, an antibiotic. We incorperated the drugs separately at 1% and 5% of weight percentage into our polyesters, Alanine(70)-Coumarin(30)-Succinic acid (Ala) and Phenylaniline(70)-Coumarin(30)-Succinic acid (Phe). The polyesters with different pendant groups, analogous to alanine and phenylalanine, were synthesized by carbodiimide-mediated polyesterification2. The UV crosslinked samples in PBS were placed in an incubator shaker at 37°C. Release of the diclofenac drug in Phe on average was 0.6% every hour for the first 6 hours, after 48 hours cumulative release was 15%. On the other hand, the cumulative release of drug in Ala could reach as high as 22% within 100 min. Our preliminary results suggest that the drug loaded scaffolds, Ala or Phe, showed different release profiles which can be customized to the desired drug release. In the future works, we will use rheology to obtain the optimum percentage of the drugs into the polymer and test drug release in 3D printed scaffolds.

[1] Boateng, J.; et al. A Review. J. Pharm. Sci. 2015, 104 (11), 3653–3680. [2] Gokhale, S.;et al Biomacromolecules 2013, 14 (8), 2489–2493.

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47) Optical Trapping to Investigate Cilia Mechanics

Jacob Duckworth Michigan State University Dr. Andrew Resnick Cleveland State University

Primary cilia are ubiquitous in the human body at cell-fluid interfaces. It has recently been proposed that these structures act as flow sensors, transducing mechanical flow energy into biological signaling often involving Ca2+. We hypothesize that the mechanics of primary cilia determines how these structures respond to flow, providing a mechanism for the cell to ‘tune’ the sensor. Here, an experiment was performed to characterize the stiffness (effective spring constant) of primary cilia under simulated hypoxic conditions. To do this, an optical trap was used to apply a non-contact, localized force directly to the cilium tip and hypoxia was simulated by chemically stabilizing the protein Hypoxia Inducible Factor (HIF). In this presentation, I will discuss our results as well as calibration and data analysis methods.

48) Consequence of Hydrogel Chemistry on Dry and Underwater Adhesion Megan Yankulov University of Mount Union Saranshu Singla, Amal Narayanan Dr. Ali Dhinojwala, Dr. Abraham Joy University of Akron Developing adhesives that work in wet environments has been challenging because the presence of interfacial water hinders the formation of strong bonds between adhesive and substrate. This need is critical in many areas including biomedical devices, bone regeneration, and tissue repair. Surprisingly, hydrogels have demonstrated superior underwater adhesion in several studies.The aim of the present study is to understand the adhesion of hydrogels to hydrophilic substrates in dry and wet conditions. Further, we aim to understand how the chemistry of the hydrogel influences the adhesion behavior. Polyethylene-glycol dimethacrylate (PEGDMA) and Poly(2-hydroxyethyl methacrylate) (PHEMA) gels were synthesized utilizing photopolymerization by UV irradiation. Johnson-Kendall-Roberts adhesion geometry was used to detail their adhesion in dry and wet conditions. Sum frequency generation spectroscopy (SFG) was used to provide insights on the role of water at the contact interface and enables us to understand the interaction strength of hydrogel with substrate. Our results indicate that PEGDMA displays adhesion in both dry and underwater conditions, however adhesion is significantly lower in underwater conditions. HEMA-PEGDMA results indicate increased dry adhesion when compared to PEGDMA results. However, underwater adhesion was still significantly lower. SFG results with PEGDMA gels indicate that water is present at the interface in underwater conditions which correlates with decreased adhesion values. To identify whether the signal in hydroxyl region is due to water or surface hydroxyl groups, further SFG experiments will utilize deuterated water.

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49) Enhanced Optical Clarity of Polyimide Aerogels via Fluorinated Monomer Incorporation

Melica Nikahd Lipscomb University

Dr. Stephanie Vivod NASA Glenn Research Center

Aerogels are lightweight, nanoporous materials derived from a gel in which the liquid is replaced by gas. Because of their high porosity (>90%), small pore size (10-40 nm), low density (0.1-0.2 g/cm3), and large surface area (400-850 m2/g), aerogels are excellent thermal insulators, with a thermal conductivity of 20 mW/m∙K. These properties, along with their low dielectric constants and good acoustic dampening, have allowed aerogels to become a prolific part of aerospace technology, as they can be used in applications such as inflatable aerodynamic decelerators, propellant tanks, heat shielding, insulation for EVA suits and habitats, and antenna substrates. In addition, aerogels incorporated with fluorinated monomers have shown to achieve lower dielectric constants, a greater resistance to higher temperatures, increased hydrophobicity, and enhanced optical clarity that would be ideal for replacing windows and windshields at a fraction of the weight and without the use of harmful or toxic chemical coatings. This study further explores the effects of fluorinated diamine incorporation in the polyimide structure to not only improve the thermal and mechanical properties of polyimide aerogels but also to observe the ability of a fluorinated polymer to enhance the optical clarity.

50) Creating Vectors for Transfection and Localization of Perilipin 3 in Adipocytes Alexandra K Yungblut The University of Alabama Amber R Titus Kent State University Dr. Kristy Welshhans Kent State University Dr. Edgar E Kooijman Kent State University

Obesity related disease is a major problem in the United States. Adipocytes, fat storage cells, are key to understanding such diseases. Adipocytes contain lipid droplets (LDs): specialized organelles that are critical for cellular energy regulation. To better understand these interactions around LDs, our lab focuses on LD binding proteins. LDs are composed of a hydrophobic core, a phospholipid monolayer, and binding proteins. There are two classes of LD binding proteins: Type I and Type II. Type I binding proteins remain closely associated to the LD. Type II binding proteins are recruited from the cytosol to the LD but also have other functions throughout the cell. The perilipin family of proteins contains both Type I (perilipin 1 and 2) and Type II (perilipins 3, 4 and 5) proteins, and is integral to lipid droplet formation and function. Our primary focus is on the Type II LD binding proteins, specifically perilipin 3. Perilipin 3 contains a conserved bundle of amphipathic α-helices located at its C-terminus. Previous data from our lab suggest that this C-terminal α-helix bundle on perilipin 3 has a stronger interaction with the lipid droplet monolayer than the N-terminus. To study the mechanism of the C-terminal domain, we compare the function of the full length to a truncated sequence that only has the C-terminal domain. Here, we’ve created mammalian transfection vectors for both the full-length protein and the C-terminus truncation that contain a tag for the FlAsh/ReAsh fluorescence molecule. We plan to use these vectors and fluorescence microscopy to determine the localization of the full-length protein versus the C-terminus truncation in murine adipocytes.

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51) Direct measurement of deposition of synthetic and biological colloids

Tyler Leibengood Youngstown State University Dr. Christopher Wirth Cleveland State University

Colloid deposition onto surfaces is a complex physical phenomenon apparent in certain health problems, like sickle cell disease. We use Total Internal Reflection Microscopy (TIRM) on sulfate latex beads and red blood cells to attain precise measurement of the particle deposition status. The sulfate latex beads are examined under a laminar flow where Reynold’s number is between E-6 and E-4. We measure deposition rates under sodium chloride concentrations of 10 mM, 100 mM, and 200 mM. We utilize a flow parallel to the collector, which hasn’t been considered for deposition in previous studies. While suspended in 10 mM NaCl solution, the coating density increases from 14 to 20 particles per (100 micons)2 over 16 minutes. We supplement this study by using TIRM to observe red blood cells experiencing various levels of sickle cell disease. Our primary goal is to evaluate the effectiveness of TIRM on red blood cells. We find success in defining scattering characteristics of red blood cells in a various diseased states and adsorbed conditions. We plan to implement particle tracking to characterize the behavior of our samples as they attach to the surface and apply our flow configuration to the sickle cell deposition similarly.

52) Polyacrylic Acid Adhesion Studies Onto Collagen Mickey Yu Stony Brook University Susan Kozawa Xinming Wang Gary Wnek Case Western Reserve University

To mimic the stress and relaxation that neurons exhibit during nerve stimulation and transmission, polyacrylic

acid (PAA) adhesion studies onto collagen while manipulating the environment with various salt solutions.

Adhesion of samples were measured using Lap Shear tests and T-Peel tests by ASTM standards. Lap Shear

test results indicate 3M PAA and 2.2M NaOH hydrogels are more adhesive than 3M PAA-H hydrogels.

However as indicated by T-Peel test results, when affixed together with collagen, 3M PAA-H hydrogels are

more adhesive. Salt solutions were found to be able to affect the size and adhesion of hydrogels. Lap Shear

test results also suggest 3M PAA-H hydrogel and collagen sample that was in 1M NaCl solution is more

adhesive than 3M PAA-H hydrogel and collagen sample in 1M CaCl2 solution. The increase of adhesion is

most likely attributed to calcium’s greater ionic strength. We have embedded PAA-H beads into extracellular

matrix (ECM), and they did not adhere very well to the ECM as predicted. Further investigation is required, and

it is proposed that EDC/NHS coupling may be necessary to strengthen the adhesion between 3M PAA-H

hydrogels and collagen within the ECM.

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53) Synthesis of Dual-Action, Fatty Acid-Like Ru(II) and Pt(IV) Complexes for Elimination of Cancer Stem Cells Elijah Holder Kent State University Morgan Stilgenbauer Kent State University Dr. Yaorong Zheng Kent State University

Organometallic platinum compounds are well documented for their efficacy in the treatment of various forms of cancer. Despite their obvious boon to cancer treatment, administration of drugs in this family (such as cisplatin, a common treatment in testicular cancer) suffers several pitfalls including unwanted side-effects and drug resistance. These pitfalls are all able to be overcome with organic modifications, such as the addition of a fatty-acid tail to facilitate transport by human serum albumin. This project primarily focused on the addition of a bipyridine-ruthenium complex to C16Pt, which refers to cisplatin with the aforementioned fatty-acid tail attached. The final product was retrieved following a simple ligand exchange and the structure was confirmed with an NMR spectrum, though toxicity tests on the compound are yet to have been performed.

54) Bioscaffold Weaving with Aligned Collagen Nanocomposites for Tendon Enthesis Repair Naazneen Ibtehaj The University of Texas at Austin Hyung Jin Jung Phillip McClellan Case Western Reserve University Ilaha Isali Ozan Akkus Case Western Reserve University and University Hospitals

The tendon enthesis contains distinct tissue zones, resulting in surgical complications when attempting to repair the region. In order to reduce these complications, a bioscaffold was designed to imitate the natural tissue organization of the enthesis. Collagen was extracted from animal tendon and electrochemically compacted to form collagen threads. These threads were used to weave a triphasic scaffold that includes the tendon, cartilage, and bone portions of the enthesis. Different solutions and weaving processes were tested for the best thread coherence and scaffold recovery. While a solution application method was determined, the triphasic scaffold threads unraveled during recovery. The weaving process will be further modified to successfully recover the triphasic scaffold to be used for tendon enthesis repair.

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55) Pentacene Thin Film Growth

Bradley Lockhart Ohio Northern University Dr. Jessica E. Bickel Cleveland State University

Organic electronics are typically cost effective, environmentally friendly, and can be used in flexible electronics. However, they are also less efficient than their inorganic counterparts. The efficiency of these organic molecules improves when they are ordered in a crystalline pattern. This work aims to self-assemble organic molecules in an ordered crystal using atomically ordered surfaces. Pentacene is a common organic semiconductor with a relatively high conductivity that increases when it is crystallized. The pentacene was studied by depositing it on highly ordered pyrolytic graphite (HOPG) using a thermal evaporator and characterizing it with scanning tunneling microscopy (STM). The initial depositions suffered from inconsistent growth rate readings, which were measured using a quartz crystal microbalance (QCM). We determined that the inconsistency was due to the fact that while the thermal evaporator chamber is under high vacuum, the daily pressure varied between 1 and 7x10-5 torr during the evaporation. These variations in pressure had a noticeable impact on the growth rate of the pentacene varying from 1.7 Å/s at 5.4x10-5 torr to 4.3 Å/s at 1.7x10-

5 torr for the same evaporation temperature. We subsequently developed a method to measure the growth rate immediately before the deposition circumventing the issue of the variable pressure. This was done by opening the shutter of the thermal evaporator to a specific angle so that the growth rate could be measured by the QCM without actually depositing any material on the HOPG. This method allowed us to accurately measure growth rates immediately preceding the deposition to have a more accurate measurement day-to-day. During the study of the STM data, several images showed the deposited pentacene either forming into clumps, or into seemingly more ordered track-like patterns. These images were analyzed to find the dimensions of these structures and compared to the dimensions of pentacene and previous work by other groups.

56) Synthesis of New Photoactivatable HNO Donors

Alex Lovins Indiana Wesleyan University Dr. Nicola E. Brasch Auckland University of Technology Dr. Paul Sampson and Dr. Alexander Seed Kent State University

Nitroxyl (HNO) is a physiologically important molecule that shows considerable promise as a new approach for treating congestive heart failure. Due to the extremely short lifetime of HNO, interactions between HNO and other biomolecules are very hard to study. In order to study these interactions, an HNO donor must be used. Slow-release HNO donors are generally favored for clinical treatment, whereas for kinetic studies a fast release of HNO is needed. Photolytic HNO donors offer an attractive path for rapid HNO release but are not very well developed to date.

As part of a program aimed at the development of photoactivatable HNO donors that might provide rapid generation of HNO, our lab has developed several families of target HNO donors. Among the most promising compounds prepared to date is the 6,2-HNM-based HNO donor with R=CF3, which is highly selective for photofragmentation via a pathway that leads to HNO release. Detailed mechanistic studies by collaborators Ruth Cink and Nicola Brasch suggest that, contrary to our expectation, the naphtholic OH proton may not be directly involved in the pathway leading to HNO release. To probe the role of this OH proton in the mechanism for HNO release, we have targeted the methoxy analog for its retention of the electron donating C-6 O substituent although without a transferable proton. Understanding the photochemistry seen with the methoxy analog relative to the parent naphthol analog will help us understand the mechanism of HNO release in this family of photoactivatable HNO donors.

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57) Adsorption of low molecular weight polyols in amphiphilic copolymers for biobutanol membranes

Jason Vaughn Stark State College Siyuan Li, Elizabeth A. Lewis The University of Akron Bryan D. Vogt The University of Akron

Biobutanol represents a promising alternative to ethanol that can nullify the problems of ethanol, however its production by fermentation is limited by the low maximum (<3 wt% butanol) concentration. Membranes allow for continuous removal of butanol to improve the potential productivity of biobutanol, but the interactions of the membrane with components in the fermentation broth can alter long-term performance. Earlier work has demonstrated that membranes based on addition polymers of polybutylnorbornene-ran-polyhexafluoroisopropanolnorbornene exhibit promising performance for pervaporation separation of biobutanol. Here we seek to understand how the nature of the hydrophobic comonomer that acts as the mechanical reinforcement for the membrane influences swelling and mechanical properties in aqueous butanol solutions through a systematic variation in the alkyl chain length. The swelling of the membranes and changes in mechanical properties were determined using a quartz crystal microbalance with dissipation monitoring (QCM-D). The changes in energy dissipation and frequency of the quartz sensor when immersed in aqueous solutions containing 0-3 wt % butanol were analyzed in terms of a rheological power law model. As the alkyl chain length increased from methyl to decyl, there was not a significant change in the swelling, which suggests that the hexafluoroisopropanolnorbornene controls the interactions with both butanol and water.

58) Enhancing mechanochemical activation in bulk polymers by reinforcing chain alignment

Rumbila Abdullahi Smith College Dr.Junpeng Wang University of Akron Devavrat Sathe University of Akron

Activation of mechanophores in linear polymers have been successfully achieved through ultrasonication and single molecule force spectroscopy. However, there has been limited success when attempting activation by applying force to bulk materials. It has been reported, there is a correlation between polymer chain alignment and force-induced chemical reaction of the mechanophore. Thus, due to the poor alignment of the mechanophores in the direction of applied force, there is little mechanochemical activation when force is applied to bulk polymers. To overcome this challenge, we plan to align a bulk material by using two-stage thiol-acrylate Michael addition and photopolymerization reaction that was reported by Yakacki et al. This method allows for the preparation of a highly aligned monodomain nematic liquid crystalline elastomer activation of mechanophore in bulk material. For our LCE, we intend to incorporate the mechanophore gem dichlorocyclopropane to the backbone of the LCE mesogen and exploit the highly ordered morphology of the LCE to enhance total activation of the mechanophore by application of tensile stress to the bulk material. We have found that, by placing the gem dichlorocyclopropane mechanophore in between the two benzene rings of the mesogen interferes with the mesogen’s ability to align, preventing the formation of a LC mesophase. To overcome this challenge, we intend to synthesize a diacrylate mesogen containing dichlorocyclopropane that is centered between two biphenyl units (that will act as the rigid cores), separated by alkyl spacers which should prevent the mechanophore from interfering with the alignment of the biphenyl units.

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