Other Chemistry Commons^™

Valorization Of Biopolymers And Biomass To Produce Materials For A More Circular Economy, Moira Lauer

All Dissertations

With a globally increasing population and largely unchecked consumption of raw materials, human society is on track for devastating consequences. Two industries responsible for utilizing massive amounts of raw materials and generating equally gargantuan quantities of waste are the packaging and infrastructure sectors. In 2017 in Europe, for example, packaging reached a record 173 kg of packaging waste per capita. One of the largest packaging consumers is the food industry, in which 40% of packaging is made of petroleum-derived single-use plastic, leading to a massive carbon imbalance. “The Built Environment,” on the other hand, is responsible for about 50% of …

Diffusion Of A Salt In An Aqueous Media, Aldaly Pineda Hernandez

Chemical Engineering Undergraduate Honors Theses

Diffusion is defined as the net transfer of a molecule from a high concentration region to a low concentration region. The concept of diffusion is used in a very important process called "desalination." Desalination is a separation process used to reduce the salt content dissolved in brackish water to make it suitable for human consumption, irrigation, and industrial use.

In desalination plants, it is important to monitor the constantly changing salt content of water, partly due to the diffusive effect. The main purpose of this experiment was to study the diffusion of NaCl in water at two NaCl concentrations. The …

How Student Attitudes Have Changed Toward Chemistry Due To The Implementation Of Hybrid Labs, Erica Bronwyn Mobley

ONU Student Research Colloquium

Hybrid chemistry labs in schools and universities have become much more common due to the COVID-19 pandemic. Previous research on student perceptions of chemistry has shown a correlation between their attitudes and performance in this subject that educators are still seeking to understand. This mixed methods study compared perceptions of students in traditional, in-person labs (pre-COVID, 2017) with students in a mixture of virtual and in-person labs (during COVID, 2020) over the course of a semester. The Attitude toward the Study of Chemistry Inventory (ASCI) survey was given to both cohorts of students and focused on five areas related to …

Designing Experiments: The Impact Of Peer Review Structure On Organic Chemistry Students' Experimental Designs, Katie Patterson

Department of Chemistry: Dissertations, Theses, and Student Research

To better understand how peer review can be used to support students when designing experiments, the current thesis examined how the structure of the peer review template affects the kinds of feedback students give and the revisions that they make. I utilized a quasi-experimental design to investigate the effects that the peer review template had on the outcome of an experimental design task. A sample of 195 students enrolled in an Organic Chemistry I course participated in the study. The students were divided into two groups, one of which was given a scaffolded peer review template and the other was …

Ketal-Azaborine Versus Ketal-Azaborine With A Spacer: Structural Effects On The Photophysical Properties Of Tunable Heteroaromatic Polycyclic Chromophores, Albert Campbell, Janiyah Riley, Samuel Moore, Albert Campbell

Symposium of Student Scholars

Flat-structured heteroaromatic polycyclic compounds with extended conjugated π-systems such as azaborines are in high demand in the material and imaging technology markets because of their unique features such as simultaneous tunability of fluorescence color and intensity. We have designed, synthesized, and investigated a series of novel conjugated thermally stable ketal-azaborine chromophores that contain a phenyl ring as a spacer between electronic moieties and the ketal-azaborine core as easily tunable high-luminescent organic materials. We investigated the impact of the phenyl spacer on the ketal-azaborine unit. We examined the structural effects on their photophysical properties by incorporating electron –donating and –withdrawing substituents …

Azaborine Versus Azaborine With A Spacer: Structural Effects On The Photophysical Properties Of Tunable Azaborine Chromophores, Kaia Ellis, Janiyah Riley, Lyric Gordon, Janiyah Riley

Symposium of Student Scholars

Azaborines are fascinating compounds because of their valuable and interesting optical properties making them suitable to be utilized in many optoelectronic devices. We have designed, synthesized, and investigated a series of novel conjugated thermally stable azaborine chromophores by incorporating a phenyl ring as a spacer linking the chromophore to different electronic moieties as easily tunable high-luminescent organic materials. We investigated the effect of the phenyl spacer on the azaborine unit. The substituent effects of different electronic moieties were investigated by the insertion of electron –withdrawing and –donating moieties to the phenyl spacer. We examined the role of the electron –donating …

Comparing And Contrasting Therapeutic Drugs Vs. Lifestyle Changes That Combattype-Ii Diabetes, Alexander Cline Helmuth

Chemistry & Biochemistry Student Projects

In this thesis, I will be presenting various preventive approaches to combat type-II diabetes. The focus of this paper will be comparing and contrasting therapeutic drug targets such as Metformin and Sulfonylureas that are prescribed for type-II diabetic patients versus taking preventative steps such as making lifestyle changes including weight management, physical activity, and having a balanced diet that prevents onset of type-II diabetes or helps patients manage type-II diabetes. From this paper, one will gain insight on how there are multiple approaches to combat type-II diabetes that are not in the form of the pill.

Microfluidic Paper Analytical Devices, Madison Page

Chemistry & Biochemistry Student Projects

Microfluidic paper analytical devices (µPADs) are small, paper-based matrices similar to Lab-on-a-Chip (LOC). They are capable of semi-quantitative analysis, with applications ranging from medical to environmental to food and beverage testing. Important to improving point-of-care devices (POCs), various techniques have been integrated into µPADs to customize analysis and fit different clinical situations.

The Application Of Biological Processes To Increase Energy Potential In Landfills, Ashlyn Eisenhart

Chemistry & Biochemistry Student Projects

There has been a dramatic increase in the amount of waste that we humans have created. This has been due to population growth, an increase in industrial manufacturing, along with urbanization and modernization.⁸ The number of tons of municipal solid waste entering landfills has increased from 82.5 million tons in 1960 to 146.1 million tons in 2018.¹⁷ However, thanks to recycling, composting, and energy recovery from combustion, the percentage of solid waste going to landfills has dramatically decreased, from around 93.6 to about 65.4 percent.¹⁷

Chemistry Of Toothpaste, Kayla Blanche Kirtley

Chemistry & Biochemistry Student Projects

The chemistry of toothpaste is explained, with a description of the chemical components and their mode of action in the role of toothpaste.

1st Place Contest Entry: Designing Hollow Nanogels For Drug Delivery Applications, Mo Hijazi

Kevin and Tam Ross Undergraduate Research Prize

This is Mo Hijazi's submission for the 2022 Kevin and Tam Ross Undergraduate Research Prize, which won first place. It contains their essay on using library resources, their bibliography, and a summary of their research project on hollow-core nanogels.

Mo is a second-year student at Chapman University, majoring in Biological Sciences. Their faculty mentor is Dr. Molla Islam.

Oxidation Of Thiols To Disulfides Using An Environmentally “Green” Organocatalyst And New Mechanistic Insights, Kosta V. Vlasakakis, Olivia M. White, Robert P. Reynolds, Shayne M. Weierbach, Shannon M. Weaver, Ramsey T. Ritter, Nishi H. Patel, Eric C. Hayes, Sydney Dunmire, Kyle M. Lambert

Undergraduate Research Symposium

The selective oxidation of thiols to disulfides is an area of great importance in the areas of materials and medicinal chemistry research. The production of polymers, rubber, pharmaceuticals, and the folding of proteins in biological systems all rely on the formation of disulfide bonds. Herein, we introduce a stoichiometric and electrocatalytic method for the oxidation of various pharmaceutically and biologically relevant thiols into their respective disulfides in more environmentally benign solvents such as water and alcohol solvents. The scope of the transformation was evaluated and a detailed mechanistic study involving control experiments, experimental kinetic studies, and computational investigations led to …

Synthesis And Evaluation Of 11c-Labeled Triazolones As Probes For Imaging Fatty Acid Synthase Expression By Positron Emission Tomography, James M. Kelly, Thomas M. Jeitner, Nicole N. Waterhouse, Wenchao Qu, Ethan J. Linstad, Banafshe Samani, Clarence Williams Jr., Anastasia Nikolopoulou, Alejandro Amor-Coarasa, Stephen G. Dimagno, John W. Babich

Department of Chemistry: Faculty Publications

Cancer cells require lipids to fulfill energetic, proliferative, and signaling requirements. Even though these cells can take up exogenous fatty acids, the majority exhibit a dependency on de novo fatty acid synthesis. Fatty acid synthase (FASN) is the rate-limiting enzyme in this process. Expression and activity of FASN is elevated in multiple cancers, where it correlates with disease progression and poor prognosis. These observations have sparked interest in developing methods of detecting FASN expression in vivo. One promising approach is the imaging of radiolabeled molecular probes targeting FASN by positron emission tomography (PET). However, although [¹¹C]acetate uptake by …

Chemical Reversible Crosslinking Enables Measurement Of Rna 3d Distances And Alternative Conformations In Cells, Ryan Van Damme, Kongpan Li, Minjie Zhang, Jianhui Bai, Wilson H. Lee, Joseph D. Yesselman, Zhipeng Lu, Willem A. Velema

Department of Chemistry: Faculty Publications

Three-dimensional (3D) structures dictate the functions of RNA molecules in a wide variety of biological processes. However, direct determination of RNA 3D structures in vivo is difficult due to their large sizes, conformational heterogeneity, and dynamics. Here we present a method, Spatial 2′-Hydroxyl Acylation Reversible Crosslinking (SHARC), which uses chemical crosslinkers of defined lengths to measure distances between nucleotides in cellular RNA. Integrating crosslinking, exonuclease (exo) trimming, proximity ligation, and high throughput sequencing, SHARC enables transcriptome-wide tertiary structure contact maps at high accuracy and precision, revealing heterogeneous RNA structures and interactions. SHARC data provide constraints that improves Rosetta-based RNA 3D …

Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that synthesize aminoacyl-tRNAs to facilitate translation of the genetic code. Quality control by aaRS proofreading and other mechanisms maintains translational accuracy, which promotes cellular viability. Systematic disruption of proofreading, as recently demonstrated for alanyl-tRNA synthetase (AlaRS), leads to dysregulation of the proteome and reduced viability. Recent studies showed that environmental challenges such as exposure to reactive oxygen species can also alter aaRS synthetic and proofreading functions, prompting us to investigate if oxidation might positively or negatively affect AlaRS activity. We found that while oxidation leads to modification of several residues in Escherichia coli AlaRS, unlike …

Decomposition Of Organic Peroxides And Hydrogen Peroxide By The Iron Thiolates And Related Complexes, Patrick H. Dussault, Andrew Olson

Department of Chemistry: Faculty Publications

Disclosed herein is a method of reducing or disproportionating peroxide, comprising combining an organic chalcogenide, an iron salt, and the peroxide in the presence of an additional reductant, which can be the organic chalcogenide. The method can be used to, e.g., prepare alcohols from peroxides and to disproportionate hydrogen peroxide into water and oxygen.

Effects Of Long-Term Fluoride Exposure Are Associated With Oxidative Biochemistry Impairment And Global Proteomic Modulation, But Not Genotoxicity, In Parotid Glands Of Mice, Giza Hellen Nonato Mirandai, Leidiane Alencar De Oliveira Lima, Leonardo Oliveira Bittencourt, Sa´Vio Monteiro Dos Santos, Michel Platini Caldas De Souza, Lygia Sega Nogueira, Edivaldo Herculano Corrêa De Oliveira, Marta Chagas Monteir, Aline Dionizio, Aline Lima Leite, Juliano Pelim Pessan, Juliano Pelim Pessan, Marı´Lia Afonso Rabelo Buzalaf, Rafael Rodrigues Limai

Department of Chemistry: Faculty Publications

Fluoride has become widely used in dentistry because of its effectiveness in caries control. However, evidence indicates that excessive intake interferes with the metabolic processes of different tissues. Thus, this study aimed to investigate the effects of long-term exposure to F on the parotid salivary gland of mice, from the analysis of oxidative, proteomic and genotoxic parameters.

The animals received deionized water containing 0, 10 or 50 mg/L of F, as sodium fluoride, for 60 days. After, parotid glands were collected for analysis of oxidative biochemistry, global proteomic profile, genotoxicity assessment and histopathological analyses.

The results revealed that exposure to …

Methanol Decomposition On Ni(111) And O/Ni(111), Henrik Öström, Bingjie Zhang, Tiffany Vallejo, Bryn Merrill, Jeremy Huang, Jerry Larue

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Methanol decomposition on Ni(111) surfaces has been studied in the presence and absence of oxygen using temperature-programmed desorption and temperature-dependent sum frequency generation spectroscopy. Under both conditions the C–H and O–H bonds break, forming carbon monoxide and atomic hydrogen on the surface. No C–O bond scission was observed, limiting the number of reaction pathways. The O–H bonds break first (>150 K), forming surface methoxy, followed by C–H bond breakage (>250 K). All atomic hydrogen desorbs from the surface as H2 through H+H recombinative desorption. H2 desorbs at a higher temperature in the presence of oxygen (>300 K) …

Inhibitors Of Alpha-Synuclein Aggregation, Jemil Ahmed

Electronic Theses and Dissertations

Alpha-Synuclein (αS) – a neuronal, disordered, presynaptic protein – aggregates into amyloid fibrils and accumulates in the substantia nigra pars compacta of Parkinson's Disease (PD) patients. The aggregation and accumulation of αS amyloid fibrils leads to death of dopaminergic neurons; a hallmark of PD. Although it’s not clear why αS aggregates, prior studies have found that intrastriatal injection of fibril alone is sufficient to cause PD pathology in mouse and non-human primates models. These observations implicate αS as a therapeutic target against PD.

Unfortunately, there are three caveats when attempting to target αS. First, αS is a neuronal protein expressed …

Characterization Of Cyclopropyl Synthases Involved In The Maturation Of Ribosomally Synthesized And Posttranslationally Modified Peptides, Yi Lien

Electronic Theses and Dissertations

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a large class of natural products with significant human health implications. RiPPs are synthesized from a genetically encoded precursor peptide that undergoes significant modifications by maturing enzymes, or maturases. Recently, radical-S-adenosylmethionine (rSAM) enzymes have emerged as an important family of RiPP maturases. rSAM enzymes have been shown to install ether, thioether, and carbon-carbon bonds on the precursor peptide. These modifications usually define the backbone structure of the mature RiPP. This thesis describes the characterization of a novel RiPP modification catalyzed by the radical S-adenosylmethionine enzyme TigE. TigE belongs to the TIG biosynthetic …