Physical Sciences and Mathematics Commons^™

Photochemistry Of A Series Of Weakly Coupled Dinuclear Ruthenium(Ii) Complexes, Latisha Michelle Puckett

Graduate Theses and Dissertations

An improved synthetic method was developed for symmetric ruthenium(II) polypyridine complexes with the form L2Ru(diphen)RuL2. The scope of the reaction was investigated in regards to the ligands, bridging ligands, and starting materials. Several ligands were successful in the synthesis, including 2,2’-bipyridine (bpy), 4,4’-dimethyl-2,2’-dipyridyl (dmb), 1,10-phenanthroline (phen), 4,7-diphenyl-1,10-phenanthroline (dpphen), and 3,4,7,8-tetramethyl-1,10-phenanthroline (tmphen). Ligands that did not react to form symmetric dimeric complexes were 2,2’-bipyrazine, bpz, and 2,2’-bipyrimidine, bpm.

Dpp, 2,3-bis(2-pyridyl)-pyrazine, effectively replaced diphen as the bridging ligand to produce (phen)2Ru(dpp)Ru(phen)24+. However, replacing the [Ru(CO)2Cl2]n with Ru(DMSO)4Cl2 did not prove successful. The newly developed synthesis was also applied to the synthesis of …

Interference-Free Gas-Phase Thermometry At Elevated Pressure Using Hybrid Femtosecond/Picosecond Rotational Coherent Anti- Stokes Raman Scattering, Joseph D. Miller, Chloe Elizabeth Dedic, Sukesh Roy, James R. Gord, Terrence R. Meyer

Terrence R Meyer

Rotational-level-dependent dephasing rates and nonresonant background can lead to significant uncertainties in coherent anti-Stokes Raman scattering (CARS) thermometry under high-pressure, lowtemperature conditions if the gas composition is unknown. Hybrid femtosecond/picosecond rotational CARS is employed to minimize or eliminate the influence of collisions and nonresonant background for accurate, frequency-domain thermometry at elevated pressure. The ability to ignore these interferences and achieve thermometric errors of <5% is demonstrated for N2 and O2 at pressures up to 15 atm. Beyond 15 atm, the effects of collisions cannot be ignored but can be minimized using a short probe delay (~6.5 ps) after Raman excitation, …

Chemistry And Biochemistry News, Georgia Southern University

Department of Chemistry and Biochemistry News (2015-2023)

• Faculty members from Chemistry and Biology Department Recived a Sustainability Fee Grant
• Teaching Scholarship

• CEMITURE 2015- Research Experience for Undergraduates

Chemistry Department Newsletter 2015, Ken Overway

Chemistry Department Newsletters

This document contains a summary of news and events from the chemistry department from the 2014-2015 academic year.

The Periodical Fall 2015, Southern Adventist University

the Periodical – Chemistry Department Newsletter

Volume 2, issue 2 of the Periodical includes articles about the Chemistry Department's partnership with Georgia-Cumberland Academy, a pictorial listing of December 2015 graduates, new service-learning tutoring classes, and an alumni spotlight.

Ambiguity In Speaking Chemistry And Other Stem Content: Educational Implications, Mick D. Isaacson, Michelle Michaels

Journal of Science Education for Students with Disabilities

Ambiguity in speech is a possible barrier to the acquisition of knowledge for students who have print disabilities (such as blindness, visual impairments, and some specific learning disabilities) and rely on auditory input for learning. Chemistry appears to have considerable potential for being spoken ambiguously and may be a barrier to accessing knowledge and to learning. Educators in chemistry may be unaware of, or have limited awareness of, potential ambiguity in speaking chemistry and may speak chemistry ambiguously to their students. One purpose of this paper is to increase awareness of potential ambiguity in speaking chemistry and other STEM fields …

Mining Public Databases For Discovery Of Structure And Function Within The Hotdog-Fold Thioesterase And Had Phosphatase Enzyme Families, Sarah Toews Keating

Chemistry and Chemical Biology ETDs

For my doctoral work, I have developed strategies to mine public databases for data that can be used to infer structural and functional information for the hotdog-fold and HADSF superfamilies. For the hotdog-fold superfamily, I used curated and automatically applied annotations of structure, taxonomic lineage, function, and subfamily membership from the UniProtKB, gene context and taxonomic information from the NCBI, and the results of several in-depth explorations of subfamily/function and structural class membership. Based on the distribution of the aforementioned annotations mapped onto a sequence similarity network (SSN), I applied structural assignments to sequences and/or specific function/subfamily assignments to ~143,000 …

Structure-Property Relationships At The Nano-Bio Interface: Engineering The Nanoparticle Surface For Immunomodulation, Daniel Fernando Moyano Marino

Doctoral Dissertations

Each year, a variety of novel nanomaterials are being developed with the objective of treating different diseases. However, since nanomaterials are foreign to the human body, one of the principal factors that limit their use is the encounter with the first line of defense from the body: the immune system. If this interaction is not taken into account, an undesired recognition takes place and the efficiency of nanoparticle based therapies is dramatically reduced. As such, understanding the rules that govern this recognition is of prime importance in the field of nanomedicine. Following this line of thoughts (the driving force), the …

Metal-Ligand Cooperative Catalysis And Methods For Metal Removal From Organic Transformations, John-Paul J. Bow

Electronic Thesis and Dissertation Repository

Organometallic catalysis has revolutionized the synthesis of complex organic molecules. Methods for C-C, C-X and C-H bond formation and cleavage are exploited throughout the areas of fine chemicals synthesis, with major applications for pharmaceuticals. This situation raises duel challenges: 1) high-performance catalysts for environmentally and economically sustainable synthesis and 2) efficient methods of catalyst (i.e. metal) removal must be identified. This work tackles both of these areas. The highly tunable cooperative P^R₂N^R'₂ ligands have been implemented for the first time for catalytic organic transformations. I show that [Ru(Cp)(P^tBu₂N^Bn₂)(MeCN)][PF_{6 …}

Morphology-Property Relationship For Binary Organic Thin Films, Alyssa Lynn Griffin

Master's Theses

Organic thin films can be readily mass-produced through solution-based fabrication methods including ink-printing and solution-casting because their light weight, flexibility, and inexpensive sources. Their applications range from organic field-effect transistors (OFET), organic solar cells (OSC), to organic light emitting diodes (OLEDs). Compared with pure component films, binary organic thin films (BOTF) allows for novel characteristics and specialized features to handle more demanding tasks. Due to the complex intermolecular interactions in BOTF, various microscopic phases with different morphological and electronic properties may be formed and this information is difficult to extract through conventional bulk measurements.

Organic thin films can be readily …

Removal Of Pb And H2s From Acs Test Procedure For Meta-Phosphoric Acid, Christopher Atlas, Ron Lacock

Student Scholar Symposium Abstracts and Posters

In the pursuit of green chemistry, adequate substitutes for lead acetate and hydrogen sulfide were investigated for use in the ACS test procedure for stabilizer in meta-phosphoric acid. In the current ACS procedure lead acetate is used to form insoluble lead phosphate. In order to remove lead from the solution lanthanum chloride was investigated with positive results. Hydrogen Sulfide is currently used to precipitate lead by forming insoluble lead sulfide. Several substitutes including oxalic acid and sulfuric acid were investigated. Preliminary testing showed that lanthanum chloride and oxalic acid are sufficient in precipitating phosphate and lead out of the sample …

Relative Reaction Rates Of The Amino Acids Cysteine, Methionine, And Histidine With Analogs Of The Anti-Cancer Drug Cisplatin, Cynthia A. Tope

Mahurin Honors College Capstone Experience/Thesis Projects

We are studying the reaction of analogs of the anticancer drug cisplatin with amino acids that differ in size and shape. The reaction of cisplatin with proteins likely precedes reaction with DNA in the body, forming a variety of products that may be toxic to the human body. The size and shape of the platinum(II) complexes often affects the rate of reaction with proteins, more so than with DNA. In this study, triamine cisplatin analogs are reacted with the amino acids cysteine, methionine, and histidine simultaneously. These reactions are monitored by NMR spectroscopy. The effect of the bulk of the …

Facile Method For Large Scale Alignment Of One Dimensional Nanoparticles And Its Biomedical Application, Sheng Feng

Theses and Dissertations

Topographical cues can profoundly affect cellular behaviors. This thesis investigate how to utilize the topographical cues generated by two techniques, flow assembly and electrospinning, to regulate cellular behaviors.

First of all, a facile and robust method to align one-dimensional (1D) nanoparticles (NPs) in large scale has been developed. Using flow assembly, representative rod-like nanoparticles, including tobacco mosaic virus (TMV), gold nanorods and bacteriophage M13, have been aligned inside capillaries by controlling flow rate and substrate surface properties. The properties of 1D NPs, such as stiffness and aspect ratio, play a critical role in the alignment. Furthermore, these hierarchically organized structures …

Impact Of Ocean Acidification On Aphotic Biogeochemical Production Of Reactive Oxygen Species, Sarah Ann Murphy

Theses and Dissertations

Reactive oxygen species (ROS) are critical to global maintenance of the global organic carbon cycle, sulfur cycle, oxygen cycle, and transition metal cycles. The primary source of ROS is commonly considered to be photolysis or photochemically driven reactions, however ROS also exist in aphotic zones. A geochemical mechanism for the same in dark environments based on the tidally driven, episodic movement of anoxic groundwaters through oxidized, Fe(III) rich sediments is shown. Predictive models were developed based on in vitro experiments and tested using sediment samples collected from a saline tidal creek in the estuary at Murrell’s Inlet, South Carolina. These …

Metals On Titania/Hopg As Models For Heterogeneous Catalysts, Randima Piyumalie Galhenage

Theses and Dissertations

The work done in this thesis is mainly focused on understanding the nanoscale morphology and activity of model heterogeneous catalysts. In order to do this we design and prepare model catalytic surfaces in ultrahigh vacuum (UHV) and study these surfaces using electron and ion based microscopies and spectroscopies. The nucleation, growth and chemical activity of mono and bimetallic clusters on TiO₂(110) were investigated in order to understand how activity is influenced by cluster sizes, interactions with the oxide support and surface compositions of the bimetallic clusters. For example, Au-based and Pt-based bimetallic clusters such as Co-Au, Co-Pt, and …

Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles

University Scholar Projects

Central to the advancement of small molecule synthesis is the ability to develop methodologies that reimagine well known chemistry in a new, environmentally friendly manner. In this thesis two central themes emerge: oxoammonium salt oxidations and trifluoromethyl incorporation using fluoroform gas. Several projects have been developed surrounding oxoammonium salt chemistry, which are featured by their mild conditions, ease of use, and the metal-free, recyclable nature of the oxidant. Trifluoromethylation using fluoroform gas finds its utility in the use of a potent greenhouse gas waste product as a benchtop reagent.

Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles

Honors Scholar Theses

Central to the advancement of small molecule synthesis is the ability to develop methodologies that reimagine well known chemistry in a new, environmentally friendly manner. In this thesis two central themes emerge: oxoammonium salt oxidations and trifluoromethyl incorporation using fluoroform gas. Several projects have been developed surrounding oxoammonium salt chemistry, which are featured by their mild conditions, ease of use, and the metal-free, recyclable nature of the oxidant. Trifluoromethylation using fluoroform gas finds its utility in the use of a potent greenhouse gas waste product as a benchtop reagent.

Chemistry And Biochemistry News, Georgia Southern University

Department of Chemistry and Biochemistry News (2015-2023)

• Chemistry Students Make a Splash at GSU Research Symposium

Learning Chemistry Through Experimentation, Brent Kamba `, Dr. Jennifer Nielson

Journal of Undergraduate Research

There is a great need for students to learn scientific skills in Uganda. Very few students pass the national chemistry exams (about 40%) and even fewer go on to study science fields in higher education. The teaching methods in Uganda are a little bit old fashion where students often just learn facts and practise rote memorization. Rarely do they develop the critical and analytical skills to help them succeed in science jobs. Teachers also express that the curriculum is very theoretical, and not experimental.

Assessment Of Silk Degradation Using Pyrolysis, Conor Makepeace

Honors Projects in Science and Technology

The purpose of this research is to investigate the molecular constitution of silk and the specific causes of post-production degradation in silk material. This capstone project focused specifically on the conditions and degradation of ancient Chinese silk products provided by the Chinese National Silk Museum. Modern silk products were artificially degraded and compared to the ancient silk using Py-GC-MS and comparative analytic techniques. This investigation revealed that the ancient silk products most likely underwent degradation in elevated temperatures while in the presence of moisture and the absence of sunlight or UV radiation during long term burial.

Chemistry And Biochemistry News, Georgia Southern University

Department of Chemistry and Biochemistry News (2015-2023)

• Eagles Fly to Denver for Chemistry Presentations

A Comparison Of Student Perceptions To Actual Performance In Chemistry, Ross Hudson

Dr Ross Hudson

This research was part of a larger study into student performance in senior chemistry with regard to question type and content. This paper examines student perceptions about question type and context and compares these perceptions to actual performance. How students perceive different types of questions and how it influences their self-belief and motivation were the focus of this study. Student responses to different styles or types of questions have been well researched over time. In this study Year 11 chemistry students were quizzed about their preferences to Multiple-Choice questions and Open Response question types and how the presence of each …

Binding-Induced, Turn-On Fluorescence Of The Egfr/Erbb Kinase Inhibitor, Lapatinib, James N. Wilson

James N Wilson

We report the photophysical properties, binding-induced turn-on emission, and fluorescence imaging of the cellular uptake and distribution of lapatinib, an EGFR/ERBB inhibitor. Lapatinib, a type II, i.e. inactive state, inhibitor that targets the ATP binding pocket of the EGFR family of receptor tyrosine kinases. DFT calculations predict that the 6-furanylquinazoline core of lapatinib should exhibit an excited state with charge transfer character and an S0 to S1 transition energy of 3.4 eV. Absorption confirms an optical tran- sition in the near UV to violet, while fluorescence spectroscopy shows that photoemission is highly sensi- tive to solvent polarity. The hydrophobicity of …

The Creation And Evaluation Of Novel Canine Training Aids For Cocaine Using Molecularly Encapsulated Sol-Gel Polymers And An Investigation Of Canine Field Accuracy, Michelle Cerreta

FIU Electronic Theses and Dissertations

Biological detectors, such as canines, are valuable tools used for the rapid identification of illicit materials. However, recent increased scrutiny over the reliability, field accuracy, and the capabilities of each detection canine is currently being evaluated in the legal system. For example, the Supreme Court case, State of Florida v. Harris, discussed the need for continuous monitoring of canine abilities, thresholds, and search capabilities. As a result, the fallibility of canines for detection was brought to light, as well as a need for further research and understanding of canine detection. This study is two-fold, as it looks to not only …

Science Classics, Mark Masthay

Mark Masthay

An essay on the impact of the works in the Imprints and Impressions: Milestones in Human Progress, an exhibition of rare books from the collection of Stuart Rose. Exhibition was held Sept. 29-Nov. 9, 2014, at the University of Dayton.

Integrating Arsenic-Related Environmental Topics Into The Education Of The Next Generation Of Citizens For Arsenic-Hit Communities: Awareness And Mobilization, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.

The Importance Of Context: An Exploration Of Factors Influencing The Adoption Of Student-Centered Teaching Among Chemistry, Biology, And Physics Faculty, Travis J. Lund, Marilyne Stains

Chemistry Department: Faculty Publications

Background: Research at the secondary and postsecondary levels has clearly demonstrated the critical role that individual and contextual characteristics play in instructors’ decision to adopt educational innovations. Although recent research has shed light on factors influencing the teaching practices of science, technology, engineering, and mathematics (STEM) faculty, it is still not well understood how unique departmental environments impact faculty adoption of evidence-based instructional practices (EBIPs) within the context of a single institution. In this study, we sought to characterize the communication channels utilized by STEM faculty, as well as the contextual and individual factors that influence the teaching practices …

Theoretical Examination Of Solvent And R Group Dependence In Gold Thiolate Nanoparticle Synthesis, Suzanne M. Neidhart, Brian M. Barngrover, Christine M. Aikens

Faculty Publications

The growth of gold thiolate nanoparticles can be affected by the solvent and the R group on the ligand. In this work, the difference between methanol and benzene solvents as well as the effect of alkyl (methyl) and aromatic (phenyl) thiols on the reaction energies and barrier heights is investigated theoretically. Density functional theory (DFT) calculations using the BP86 functional and a triple ζ polarized basis set show that the overall reaction favors methylthiol over phenylthiol with reaction energies of −0.54 and −0.39 eV in methanol, respectively. At the same level of theory, the methanol solvent is favored over the …

Characterization Of Cold Drawn Poly L Lactic Acid By Raman Spectroscopy And Raman Hyperspectral Imaging, Ramya Sudha Muttavarapu

ETD Archive

Artificial modulation of bone growth and repair processes is an important area of current research. Studies have established that the micro mechanical and bulk physical properties of a polymer implant influence its performance behavior and degradation patterns in the body. One important parameter for the class of polymers known as polylactides is the degree of crystalline character. Hence, studying the bulk and micro crystalline composition of an important polymer implant, Poly-L-Lactic acid is the objective of this study. Poly-L-Lactic acid has elastic properties that can be tailored to resemble natural bone and its reaction to mechanical stress. Varying degrees of …

Photogenerated O-Azaxylylenes: Mechanistic Studies And Synthetic Applications, William Cole Cronk

Electronic Theses and Dissertations

This research sets out to build upon excited state o-azaxylylene cycloaddition. The mechanism behind the excitation and cycloaddition process of photogenerated o-azaxylylenes was determined experimentally. Time-correlated single-photon counting, steady-state spectroscopy, triplet quenching experiments, and quantum yield studies provided evidence suggesting that excited state intramolecular proton transfer is followed by intersystem crossing and stepwise addition to the tethered unsaturated pendant.

In keeping with the principles of diversity oriented synthesis, a modular approach was taken to gain access to a diverse array of N,O,S-Polyheterocycles which were modified postphotochemically via Suzuki coupling to yield fused biaryls. Cycloaddition products, outfitted with halogens …