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Bridging The Molecular/Material Divide: An Investigation Into The Properties Of Polyesters, Terra Marie M. Jouaneh May 2019

Bridging The Molecular/Material Divide: An Investigation Into The Properties Of Polyesters, Terra Marie M. Jouaneh

Senior Honors Projects

By definition, polymers consist of large molecules composed of small, repeating units called monomers. These monomers give characteristic material properties to polymers, whether they be the melting point, the folding character, or the inherent stability. Many of the objects we encounter on a daily basis are composed of polymers. These polymers may be synthetic, such as the plastic in disposable bags, or natural, like glycogen in the liver. Recent developments in biotechnology have used synthetic polymers in drug delivery, contact lenses, and even organ transplants. Polyesters, in particular, have been utilized pharmacologically due to their biodegradable properties. Understandably, not all …

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Molecular Machines: Synthesis, Modeling, And Applications, Syd Kotar May 2019

Molecular Machines: Synthesis, Modeling, And Applications, Syd Kotar

Student Scholar Symposium Abstracts and Posters

While some of the smallest, most useful machines known to science are the biological molecules that keep living organisms alive, there is a growing advancement of the creation of artificial molecules that have the same function and are more efficient. Molecular machines were invented in 1983 when scientists in France created a machine formed of two interlinked molecular rings. In 2016, the Nobel prize in chemistry was awarded to Feringa, Stoddart, and Sauvage who finally documented molecular machines and put them into energy‐filled states in which their movements could be controlled. From this, molecular machines became known as a group …

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Spontaneous Advent Of Genetic Diversity In Rna Populations Through Multiple Recombination Mechanisms, Benedict A. Smail, Bryce E. Clifton, Ryo Mizuuchi, Niles Lehman May 2019

Spontaneous Advent Of Genetic Diversity In Rna Populations Through Multiple Recombination Mechanisms, Benedict A. Smail, Bryce E. Clifton, Ryo Mizuuchi, Niles Lehman

Chemistry Faculty Publications and Presentations

There are several plausible abiotic synthetic routes from prebiotic chemical materials to ribonucleotides and even short RNA oligomers. However, for refinement of the RNA World hypothesis to help explain the origins of life on the Earth, there needs to be a manner by which such oligomers can increase their length and expand their sequence diversity. Oligomers longer than at least 10-20 nucleotides would be needed for raw material for subsequent natural selection. Here, we explore spontaneous RNA-RNA recombination as a facile means by which such length and diversity enhancement could have been realized. Motivated by the discovery that RNA oligomers …

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Visible Light-Triggered Carbon Monoxide-Releasing Molecules, Marina Popova May 2019

Visible Light-Triggered Carbon Monoxide-Releasing Molecules, Marina Popova

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon monoxide (CO) is now well established as one of the signaling molecules in higher organisms, including humans. Due to its physiological roles, CO is now accepted as a potential therapeutic agent. The use of CO gas has been studied in multiple clinical trials. Vasodilation, anti-inflammatory, anti-apoptotic, anti-proliferative and cytoprotective effects are just a few of the pharmacological actions attributed to CO gas in various models of diseases. Use of inhaled CO gas as a therapeutic has many limitations which necessitate the development of a new approach for CO delivery. In order to handle CO safely, compounds that release CO …

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Kinetic Study Of Silver Nanoparticle Formation, Steven A. Diaz Apr 2019

Kinetic Study Of Silver Nanoparticle Formation, Steven A. Diaz

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

With the increased use of silver nanoparticles in modern day applications, kinetic information on the mechanism of their formation is useful for further studies on its reactivity in a biological environment. Silver nanoparticles were synthesized using a modified Turkevich method. The synthesized nanoparticles were characterized using UV-Visible spectroscopy. The data obtained were plotted as a function of time, and rate constants for the nucleation (k1) and autocatalytic surface growth (k2) were extracted. Comparing the k1 (~10-3) and k2 (~10-1) values supports a two-step mechanism of slow nucleation and fast autocatalytic …

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Influence Of Monomer Deformation On The Competition Between Two Types Of Σ-Holes In Tetrel Bonds, Rafal Wysokiński, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner Apr 2019

Influence Of Monomer Deformation On The Competition Between Two Types Of Σ-Holes In Tetrel Bonds, Rafal Wysokiński, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

One of several tetrel (T) atoms was covalently attached to three F atoms and a substituted phenyl ring. A NH3 base can form a tetrel bond with TF3C6H2R3(T = Si, Ge, Sn, Pb; R = H, F, CH3) in a position opposite either an F atom or the ring. The σ-hole opposite the highly electron-withdrawing F (T-F) is more intense than that opposite the ring (T-C). However, when the Lewis base deforms from a tetrahedral to a trigonal bipyramidal shape so as to accommodate the base, it is the T-C σ-hole that is more intense. Accordingly, it is the T-C …

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Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Nikolay V. Tkachenko, Alexander I. Boldyrev Apr 2019

Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Nikolay V. Tkachenko, Alexander I. Boldyrev

Chemistry and Biochemistry Faculty Publications

Nonagermanide clusters are widely used in inorganic synthesis and are actively studied by experimentalists and theoreticians. However, chemical bonding of such versatile species is still not completely understood. In our work we deciphered a bonding pattern for various experimentally obtained nonagermanide species. We localized the electron density via the AdNDP algorithm for the model structures ([Ge9]4−, [Ge9{P(NH2)2}3]−, Cu[Ge9{P(NH2)2}3] and Cu(NHC)[Ge9{P(NH2)2}3]) and obtained a simple and chemically intuitive bonding pattern which …

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Generalizing Metallocene Mechanochemistry To Ruthenocene Mechanophores, Ye Sha, Yudi Zhang, Enhua Xu, C Wayne Mcalister, Tianyu Zhu, Stephen L. Craig, Chuanbing Tang Apr 2019

Generalizing Metallocene Mechanochemistry To Ruthenocene Mechanophores, Ye Sha, Yudi Zhang, Enhua Xu, C Wayne Mcalister, Tianyu Zhu, Stephen L. Craig, Chuanbing Tang

Faculty Publications

Recent reports have shown that ferrocene displays an unexpected combination of force-free stability and mechanochemical activity, as it acts as the preferred site of chain scission along the backbone of highly extended polymer chains. This observation raises the tantalizing question as to whether similar mechanochemical activity might be present in other metallocenes, and, if so, what features of metallocenes dictate their relative ability to act as mechanophores. In this work, we elucidate polymerization methodologies towards main-chain ruthenocene-based polymers and explore the mechanochemistry of ruthenocene. We find that ruthenocene, in analogy to ferrocene, acts as a highly selective site of main …

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Synthesis And Application Of A Magnetic Nanoparticle Based Nano-Complex For Targeted Cell Death In Glioblastoma Multiforme Cells, Matthew Tovar Apr 2019

Synthesis And Application Of A Magnetic Nanoparticle Based Nano-Complex For Targeted Cell Death In Glioblastoma Multiforme Cells, Matthew Tovar

Departmental Honors & Graduate Capstone Projects

In the last ten years, there has been little advancement in the treatment of the aggressive brain cancer Glioblastoma Multiforme (GBM). This work describes the synthesis of a superparamagnetic iron oxide (SPION)-based nanotheraputic complex for use in targeting and killing aggressive mesenchymal GBM cells. The average sizes (and therefore magnetic properties) of the synthesized SPIONs are precisely tailored via a novel time-controlled approach utilizing a previously described electrochemical reaction. Through this synthetic method, the optimal particle size (OPS) where maximal thermal energy is released upon stimulation with an external magnetic field was determined to be 21 nm. The nano-complex was …

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High-Efficiency Nitrite Sensor Based On Cop Nanowire Array, Fu-Ling Zhou, Xiao-Li Xiong, Xu-Ping Sun Apr 2019

High-Efficiency Nitrite Sensor Based On Cop Nanowire Array, Fu-Ling Zhou, Xiao-Li Xiong, Xu-Ping Sun

Journal of Electrochemistry

Nitrite has a negative impact on the environment and human health. The long-term consumption of nitrite-containing foods has a carcinogenic risk. Therefore, the analysis and detection of nitrite are important. It is of great significance to develop high-efficiency electrocatalysts to achieve high sensitivity and selectivity for nitrite detection. The cobalt phosphide nano-array (CoP/TM) was obtained by hydrothermal and low-temperature phosphating. The electrochemical test results show that the constructed CoP/TM was a highly efficient electrochemical reduction nitrite catalyst with the excellent sensing performance and response time less than 3 s, as well as the linear detection range of 1.0 μmol·L-1 …

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Low Molecular Weight Fluorescent Probes (Lmfps) To Detect The Group 12 Metal Triad, Ashley D. Johnson, Rose M. Curtis, Karl J. Wallace Apr 2019

Low Molecular Weight Fluorescent Probes (Lmfps) To Detect The Group 12 Metal Triad, Ashley D. Johnson, Rose M. Curtis, Karl J. Wallace

Faculty Publications

Fluorescence sensing, of d-block elements such as Cu2+, Fe3+, Fe2+, Cd2+, Hg2+, and Zn2+ has significantly increased since the beginning of the 21st century. These particular metal ions play essential roles in biological, industrial, and environmental applications, therefore, there has been a drive to measure, detect, and remediate these metal ions. We have chosen to highlight the low molecular weight fluorescent probes (LMFPs) that undergo an optical response upon coordination with the group 12 triad (Zn2+, Cd2+, and Hg2+), as these metals have …

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Sensitive And Reusable Electrogenerated Chemiluminescence Aptasensor Fabricated By Electrochemically Double Covalent Coupling Method For The Detection Of Cocaine, Xiao-Feia Wang, Tinga Zhang, Bing Wang, Hong-Lan Qi, Cheng-Xiao Zhang Apr 2019

Sensitive And Reusable Electrogenerated Chemiluminescence Aptasensor Fabricated By Electrochemically Double Covalent Coupling Method For The Detection Of Cocaine, Xiao-Feia Wang, Tinga Zhang, Bing Wang, Hong-Lan Qi, Cheng-Xiao Zhang

Journal of Electrochemistry

A double covalent coupling method based on click chemistry and diazonium chemistry was developed for the fabrication of a sensitive and reusable electrogenerated chemiluminescence (ECL) aptasensor. As a proof-of-concept, cocaine was chosen as a model target, and a specific aptamer was chosen as a recognition molecule element, while ruthenium complex derivative (Ru1) as an ECL signal compound. The ECL aptasensor was fabricated by electrochemically diazotizing a phenylazide on the surface of a glassy carbon electrode, and then, coupling the alkyne functionalized Ru1-labeled cocaine aptamer through click chemistry. The ECL aptasensor was facilely used to determine cocaine in the range from …

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A Facile Strategy For Two-Step Fabrication Of Gold Nanoelectrode For In Vivo Dopamine Detection, Li-Hao Guan, Chao Wang, Wang Zhang, Yu-Lu Cai, Kai Li, Yu-Qing Lin Apr 2019

A Facile Strategy For Two-Step Fabrication Of Gold Nanoelectrode For In Vivo Dopamine Detection, Li-Hao Guan, Chao Wang, Wang Zhang, Yu-Lu Cai, Kai Li, Yu-Qing Lin

Journal of Electrochemistry

In vivo monitoring neurochemicals with microelectrode is invasive and the damage to brain tissue may inevitably cause disturbance signals physiologically to the measurement. It is of great importance to reduce the electrode size and to decrease the damage. This study demonstrates a novel nanoelectrode preparation methodology for in vivo monitoring dopamine (DA) fluctuation in the living brain of rats with high dependability. The fabrication process of the gold nanoelectrode involving a few minutes consists of only two steps: 1) growing gold nanoseeds on surface of tip of glassy capillary by ion sputtering; 2) wet depositing a continuous conductive gold film …

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Preparation And Electrocatalytic Oxygen Reduction Performance Of Self-Doped Sludge-Derived Carbon, Ya-Li Ye, Wei-Ming Feng, Ge Li, Zhen-Chao Lei, Chun-Hua Feng Apr 2019

Preparation And Electrocatalytic Oxygen Reduction Performance Of Self-Doped Sludge-Derived Carbon, Ya-Li Ye, Wei-Ming Feng, Ge Li, Zhen-Chao Lei, Chun-Hua Feng

Journal of Electrochemistry

The development of low-cost, high-performance cathode catalysts is critical for practical application of fuel cells. Here, the N, P-doped porous graphene-like carbon with outstanding oxygen reduction reaction (ORR) performance was synthesized by pyrolysis of surplus sludge, which functioned as a self-doped, self-activated, and self-templated precursor by acclimation with continuous feedings of phenol. The results show that the amounts of microorganisms were enriched after acclimation, with increasing contents of N, P, Fe, as well as C atoms. The increasing pyrolysis temperature resulted in the formation of an ordered graphitic structure, however, the excessively high temperature induced the drop in the amounts …

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Recent Progress Of Electrochemiluminescence Sensors Based On Electrically Heated Electrode, Hui-Fang Zhang, Yi-Ting Chen, Fang Luo, Zhen-Yu Lin, Guo-Nan Chen Apr 2019

Recent Progress Of Electrochemiluminescence Sensors Based On Electrically Heated Electrode, Hui-Fang Zhang, Yi-Ting Chen, Fang Luo, Zhen-Yu Lin, Guo-Nan Chen

Journal of Electrochemistry

Electrochemiluminescence (ECL) has broad application in the fields of environmental monitoring and biological analysis due to its intrinsic advantages such as excellent versatility, good detection sensitivity, and high specificity. The intensity of ECL can be influenced by temperature variation in the ECL quantum efficiency and the rate of electrochemical reaction. However, traditional temperature control is commonly realized through bulk solutions heating, which is complicated and unfavorable for detection when the volatile and thermally unstable materials existed. In order to address these problems, electrically heated electrodes are used to adjust the temperature desired. The major character of this technique lies in …

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Electropolymerization Of Polyaniline In The Presence Of Ferricyanide, Farhad Akrami, Lucas Marinelli, Ryan M. West Apr 2019

Electropolymerization Of Polyaniline In The Presence Of Ferricyanide, Farhad Akrami, Lucas Marinelli, Ryan M. West

Creative Activity and Research Day - CARD

Here, we demonstrate that electropolymerization of aniline in the presence of ferricyanide leads to incorporation of the ferricyanide anions into the resulting polyaniline (PANI) film and an increase of the apparent deposition rate. Simultaneous cyclic voltammetry (CV) and quartz crystal microbalance (QCM) measurements in background electrolyte show a change in counter ion ingress/egress during oxidation and reduction of the film: an “inverted” mass transport behavior is observed, suggesting a cation-exchange mechanism for maintaining charge neutrality during oxidation of the leucoemeraldine to emeraldine state of the polymer. The behavior of the PANI-ferricyanide film is compared with films polymerized in the presence …

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Effect Of Salt Concentration On Electrochemical Detection Of Dna, Ziming Dong, Eddie Madrigal, Ryan West Dr. Apr 2019

Effect Of Salt Concentration On Electrochemical Detection Of Dna, Ziming Dong, Eddie Madrigal, Ryan West Dr.

Creative Activity and Research Day - CARD

Electrochemical approaches for biological sensing offer the potential advantages of facile sample preparation, fast response times, ease of parallel and multiplexed measurements, and the possibility of miniaturization (of sample sizes, electrodes, and associated electronics). All of these factors contribute towards the feasibility of electrochemical methods in biological sensing and analysis. This potential has already been achieved with the commercialization of blood glucose meters, which often rely on an electrochemical transduction mechanism. We have previously demonstrated the ability to electrochemically detect and differentiate complementary and mismatched DNA using our method of melting DNA duplexes at electrified gold surfaces, i.e. e-melting. Recently, …

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Hplc-Based Automated Synthesis: Building Blocks For The Development Of New Technologies, Hayley B. Steber, Matteo Panza Apr 2019

Hplc-Based Automated Synthesis: Building Blocks For The Development Of New Technologies, Hayley B. Steber, Matteo Panza

Undergraduate Research Symposium

Use of automated technologies is of increasing interest in glycosciences.1 Among the new methodologies, a number of recent advancements have emerged in the area of solid-phase oligosaccharide synthesis.2-3 Demchenko and Stine developed a synthesizer based on a commercial HPLC instrument that was recently improved by the implementation of the autosampler for the delivery of glycosylation promoters.4 Despite the added versatility, the system still lacks complete automation. The foundations of glycan syntheses are acceptors and donors, grouped together under the general term of building blocks. Presented herein is the synthesis of the building blocks of the rhamno and galacto series. We …

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Interactions Of (My) 6 (M = Zn, Cd; Y = O, S, Se) Quantum Dots With N-Bases, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner Apr 2019

Interactions Of (My) 6 (M = Zn, Cd; Y = O, S, Se) Quantum Dots With N-Bases, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

(MY)6 clusters, with M = Zn and Cd and Y = O, S, Se, form double-layer drum-like structures containing M–Y covalent bonds. The positive regions near the M atoms attract the N atom of both NH3 and NMe3 so as to form a noncovalent M···N bond. This bond is quite strong, with interaction energies exceeding 35 kcal/mol. The bond strength diminishes with reduced electronegativity of the Y atom (O > S > Se) and is stronger for M = Zn than for Cd. Trimethylation of the base enhances the bond strength. The interaction is dominated by the electrostatic component …

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Coumarins And P450s, Studies Reported To-Date, Maryam Foroozesh, Jayalakshmi Sridhar, Navneet Goyal, Jiawang Liu Apr 2019

Coumarins And P450s, Studies Reported To-Date, Maryam Foroozesh, Jayalakshmi Sridhar, Navneet Goyal, Jiawang Liu

Faculty and Staff Publications

Cytochrome P450 enzymes (CYPs) are important phase I enzymes involved in themetabolism of endogenous and xenobiotic compounds mainly through mono-oxygenation reactions into more polar and easier to excrete species. In addition to their role in detoxification, they play important roles in the biosynthesis of endogenous compounds and the bioactivation of xenobiotics. Coumarins, phytochemicals abundant in food and commonly used in fragrances and cosmetics, have been shown to interact with P450 enzymes as substrates and/or inhibitors. In this review, these interactions and their significance in pharmacology and toxicology are discussed in detail.

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Department Of Chemistry And Biochemistry 24th Departmental Symposium In Conjunction With The Petersheim Academic Exposition, Seton Hall University Apr 2019

Department Of Chemistry And Biochemistry 24th Departmental Symposium In Conjunction With The Petersheim Academic Exposition, Seton Hall University

Petersheim Academic Exposition

No abstract provided.

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Detecting Zn(Ii) Ions In Live Cells With Near-Infrared Fluorescent Probes., Mingxi Fang, Shuai Xia, Jianheng Bi, Travis P Wigstrom, Loredana Valenzano, Jianbo Wang, Marina Tanasova, Rudy Luck, Haiying Liu Apr 2019

Detecting Zn(Ii) Ions In Live Cells With Near-Infrared Fluorescent Probes., Mingxi Fang, Shuai Xia, Jianheng Bi, Travis P Wigstrom, Loredana Valenzano, Jianbo Wang, Marina Tanasova, Rudy Luck, Haiying Liu

Michigan Tech Publications, Part 1

Two near-infrared fluorescent probes (A and B) containing hemicyanine structures appended to dipicolylamine (DPA), and a dipicolylamine derivative where one pyridine was substituted with pyrazine, respectively, were synthesized and tested for the identification of Zn(II) ions in live cells. In both probes, an acetyl group is attached to the phenolic oxygen atom of the hemicyanine platform to decrease the probe fluorescence background. Probe A displays sensitive fluorescence responses and binds preferentially to Zn(II) ions over other metal ions such as Cd2+ ions with a low detection limit of 0.45 nM. In contrast, the emission spectra of probe B is …

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Assessment Of Oxidative Stress In The Livers Of Rats Exposed To 2-Aminoanthracene For Twelve Weeks, John C. Stagg Apr 2019

Assessment Of Oxidative Stress In The Livers Of Rats Exposed To 2-Aminoanthracene For Twelve Weeks, John C. Stagg

Honors College Theses

Diabetes is a chronic illness that affects many people, and it’s thought that environmental exposure to certain compounds may increase its proliferation. In this study, we examine the dietary effects of 2-aminoanthracene (2AA), a polycyclic aromatic hydrocarbon (PAH), in rats, specifically as it relates to oxidative stress. Oxidative stress refers to the imbalance of reactive oxygen species (ROS) and antioxidants in living systems; it has been shown to contribute to type-1 diabetes. To accomplish the study objectives rats were divided into three dietary treatment groups, control (0 mg/kg-2AA), low dose (50 mg/kg-2AA) and high dose (100 mg/kg-2AA). Rats were fed …

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The Nifz Accessory Protein Has An Equivalent Function In Maturation Of Both Nitrogenase Mofe Protein P-Clusters, Emilio Jimenez-Vicente, Zhi-Yong Yang, Julia S. Martin Del Campo, Valarie L. Cash, Lance C. Seefeldt, Dennis R. Dean Apr 2019

The Nifz Accessory Protein Has An Equivalent Function In Maturation Of Both Nitrogenase Mofe Protein P-Clusters, Emilio Jimenez-Vicente, Zhi-Yong Yang, Julia S. Martin Del Campo, Valarie L. Cash, Lance C. Seefeldt, Dennis R. Dean

Chemistry and Biochemistry Faculty Publications

The Mo-dependent nitrogenase comprises two interacting components called the Fe protein and the MoFe protein. The MoFe protein is an α2β2 heterotetramer that harbors two types of complex metalloclusters, both of which are necessary for N2reduction. One type is a 7Fe-9S-Mo-C-homocitrate species designated FeMo-cofactor, which provides the N2-binding catalytic site, and the other is an 8Fe-7S species designated the P-cluster, involved in mediating intercomponent electron transfer to FeMo-cofactor. The MoFe protein's catalytic partner, Fe protein, is also required for both FeMo-cofactor formation and the conversion of an immature form of P-clusters to the …

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Best Organic Chemistry Practices In The Midwest, Claire Van Der Bosch Apr 2019

Best Organic Chemistry Practices In The Midwest, Claire Van Der Bosch

Honors Theses

Organic Chemistry is a gateway course to a handful of courses in higher chemical education. Unfortunately, it is notorious for its high-fail, high-withdrawal, and high-drop rate and has a reputation for being time-consuming, with difficult concepts that are oftentimes new to students. It is often taught in a two-semester sequence, with the courses named Organic I and Organic II, and both courses have a lab component. At Western Michigan University, the fail rate for these two courses are 53.5% and 36.9%, respectively. Most higher education institutions are certified with the American Chemical Society (ACS) and given a skeleton of a …

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Nanogels And Microgels: From Model Colloids To Applications, Recent Developments, And Future Trends, Mattias Karg, Andrij Pich, Thomas Hellweg, Todd Hoare, L. Andrew Lyon, J. J. Crassous, Daisuke Suzuki, Rustam A. Gumerov, Stefanie Schneider, Igor I. Potemkin, Walter Richtering Apr 2019

Nanogels And Microgels: From Model Colloids To Applications, Recent Developments, And Future Trends, Mattias Karg, Andrij Pich, Thomas Hellweg, Todd Hoare, L. Andrew Lyon, J. J. Crassous, Daisuke Suzuki, Rustam A. Gumerov, Stefanie Schneider, Igor I. Potemkin, Walter Richtering

Engineering Faculty Articles and Research

Nanogels and microgels are soft, deformable, and penetrable objects with an internal gel-like structure that is swollen by the dispersing solvent. Their softness and the potential to respond to external stimuli like temperature, pressure, pH, ionic strength, and different analytes make them interesting as soft model systems in fundamental research as well as for a broad range of applications, in particular in the field of biological applications. Recent tremendous developments in their synthesis open access to systems with complex architectures and compositions allowing for tailoring microgels with specific properties. At the same time state-of-the-art theoretical and simulation approaches offer deeper …

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On The Capability Of Metal-Halogen Groups To Participate In Halogen Bonds, Steve Scheiner Apr 2019

On The Capability Of Metal-Halogen Groups To Participate In Halogen Bonds, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

A number of halogen (X) atoms were covalently attached to a metal (M) and the ability of the X atom to act as electron acceptor in a halogen bond to nucleophile NCH was assessed. Both Cl and Br were considered as halogen atom, with NH3 and CO as other ligands attached to the metal. Metals tested were Ti, Mn, and Zn in various combinations of oxidation state, coordination, and overall charge. In the majority of cases, the strong electron-releasing power of the metal imbues the halogen atom with a high negative partial charge and minimizes the development of a σ-hole. …

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The Effects Of Climate Change And Forest Disturbances On Terpene Production Of White Pine (Pinus Strobus) And Red Pine (Pinus Resinosa) In Northern Michigan, Troy Dehagen Apr 2019

The Effects Of Climate Change And Forest Disturbances On Terpene Production Of White Pine (Pinus Strobus) And Red Pine (Pinus Resinosa) In Northern Michigan, Troy Dehagen

Honors Theses

The secondary impacts that climate change may have on the interactions between forests and the atmosphere through forest disturbances is of increasing interest as the climate continues to change. Anthropogenic climate change, which is a direct result of coal and fossil fuel emissions, is likely to impact forest ecology through increased temperatures and extreme precipitation events, thus increasing the frequency and severity of climate-induced forest disturbances. Forest disturbances may have a secondary impact on the production and emission of biogenic volatile organic compounds (BVOC) within forests. In the presence of oxides of nitrogen (NOx) produced from fossil fuel …

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Nanostructuring Organic/Inorganic Multicomponent Composites For Solution Processable Solar Cells, Brad W. Watson Apr 2019

Nanostructuring Organic/Inorganic Multicomponent Composites For Solution Processable Solar Cells, Brad W. Watson

Chemistry and Chemical Biology ETDs

The current state of organic photovoltaics is centered on systems of polymeric donors and some type of acceptor molecule (i.e. fullerene) formed into an active layer that adopts a bulk-heterojunction morphology. Although these devices have come a far way from where they were when they were first discovered in the 1980’s much work is still needed to make them a viable technology. Two of the limitations of this type of devices revolve around the relatively narrow absorption window of the components and lack of control over the morphology after the film is cast. To overcome these shortcomings there are several …

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Mechanistic Studies And Derivative Effects In 1, 3, 4- Oxadiazole Synthesis Via Cyclodehydration Reactions, Evan Huggins Apr 2019

Mechanistic Studies And Derivative Effects In 1, 3, 4- Oxadiazole Synthesis Via Cyclodehydration Reactions, Evan Huggins

Undergraduate Honors Thesis Projects

In the world of pharmaceutical synthesis, research to combat foreign pathogens is always necessary. Scientists have been exploring different methods in order to synthesize the most effective compounds in antibacterial, anticancer, anti-inflammatory, and many other treatments. A key component within these versatile compounds are 1,3,4-oxadiazoles. Current methods to synthesize these compounds are inefficient. This research seeks to improve oxadiazole synthesis; however, the mechanism of this reaction is unknown. The goal of this project was to study the mechanistic pathway in the discovered, one-pot cyclodehydration synthesis of 1,3,4-oxadiazoles. In the first part of this study, a diacylhydrazine intermediate was proposed. This …

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