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2021

Chemistry

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Full-Text Articles in Physical Sciences and Mathematics

Protocol For Fabricating Electroless Nickel Immersion Gold Strain Sensors On Nitrile Butadiene Rubber Gloves For Wearable Electronics, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael Dec 2021

Protocol For Fabricating Electroless Nickel Immersion Gold Strain Sensors On Nitrile Butadiene Rubber Gloves For Wearable Electronics, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

This protocol describes the fabrication of patterned conductive gold films on nitrile butadiene rubber (NBR) gloves for wearable strain sensors using electroless nickel immersion gold (ENIG) plating, a solution-based metallization technique. The resulting NBR/ENIG films are strain sensitive; resistance measurements of a patterned sensing array can be used to map human hand motions. This protocol also describes challenges related to the ENIG process and troubleshooting steps to achieve conformal gold films for strain sensing over a large working range. For complete details on the use and execution of this protocol, please refer to Mechael et al. (2021).


Quantum Mechanics-Based Computational Chemistry Has Become A Powerful Partner In The Scientific Research Of Nitrogen-Rich Compounds, Paving The Way For Important Advances In Biochemical, Pharmacological And Other Related Fields, Dobrushe Denburg Dec 2021

Quantum Mechanics-Based Computational Chemistry Has Become A Powerful Partner In The Scientific Research Of Nitrogen-Rich Compounds, Paving The Way For Important Advances In Biochemical, Pharmacological And Other Related Fields, Dobrushe Denburg

Student Theses and Dissertations

The Computational Chemistry of Nitrogen-Rich Compounds; Insight into Pioneering Research

Nitrogen-rich functional groups have long been studied for their diversity; nitrogen can form single, double and triple bonds with itself, and will therefore exist in a very broad range of molecular arrangements. Poly-nitrogen compounds are highly energetic and electron rich, and many compounds display unique properties that allow participation in very specialized chemical reactions. Of import is their ubiquity in biological systems, and throughout the past century and currently, their biological relevance is deeply and widely explored in biochemistry and biomedicine, from their involvement in natural biological processes and complex …


The Impact Of Project-Based Learning On Students In High School Chemistry In Rural Maine, Brianna Degone Dec 2021

The Impact Of Project-Based Learning On Students In High School Chemistry In Rural Maine, Brianna Degone

Electronic Theses and Dissertations

Project-based learning (PBL) is an instructional strategy that is promoted throughout education for its use of active learning and ability to connect to real-world applications. Studies have been conducted on PBL ranging from early elementary grades through graduate courses, however little research considers the effectiveness of PBL at the secondary science level. This thesis considers the use of PBL and describes the implementation of a PBL unit in a rural Maine 11th grade chemistry classroom. The thesis aims to better understand the impact PBL has on students’ content learning and additional skills acquired through the PBL learning process. Along with …


Development Of Bioaffinity Based Assays For Forensic Applications, Juliana Maria Agudelo Cano Dec 2021

Development Of Bioaffinity Based Assays For Forensic Applications, Juliana Maria Agudelo Cano

Legacy Theses & Dissertations (2009 - 2024)

In the field of forensic science, body fluids are a major contributor of evidence in investigations. However, body fluids are usually used only for their genetic content, overlooking its unique composition of proteins and low-molecular-weight compounds that often serve as biomarkers in clinical diagnostics. This investigation aimed to develop simple, effective, and economical models that can be used to identify different attributes of the originator. The focus of this research was to develop biocatalytic cascades that could analyze body fluids by using UV-Vis spectroscopy. These models could be implemented in forensic settings, as well as in biometric authentications. The central …


Analysis Of Ritalin Addiction And Recovery From Both A Physical And Psychological Lens, Nicole Madrigal, Tyler Marshall Nov 2021

Analysis Of Ritalin Addiction And Recovery From Both A Physical And Psychological Lens, Nicole Madrigal, Tyler Marshall

Fall Showcase for Research and Creative Inquiry

We will investigate the physical impacts, both short and long-term effects, of substance use. In doing so, we will frame an argument for the substance's addictive properties as it relates to both its physically addictive and sociological addictive properties. In doing so, a stronger understanding of how an individual can move through the stages of substance use, to abuse, and finally addiction will be reviewed. We will then address current treatment strategies for the substance and how they address or fail to address both the physical and sociological impacts of its use.


Analysis Of Fluoxetine (Prozac) Addiction And Recovery From Both A Physical And Psychological Lens, Kristen Dobek, Hannah Couch Nov 2021

Analysis Of Fluoxetine (Prozac) Addiction And Recovery From Both A Physical And Psychological Lens, Kristen Dobek, Hannah Couch

Fall Showcase for Research and Creative Inquiry

We will investigate the physical impacts both short and long term effects of of substance use. In doing so we will frame an argument for the substance's addictive properties as it relates to both its physically addictive and sociological addictive properties. In doing, so a stronger understanding of how an individual can move through the stages of substance use, to abuse, and finally addiction will be reviewed. We will then address current treatment strategies for the substance and how they address or fail to address both the physical and sociological impacts of its use.


Analysis Of Oxycontin Addiction And Recovery From Both A Physical And Psychological Lens, Meagan Munley, Carrie Flickinger Nov 2021

Analysis Of Oxycontin Addiction And Recovery From Both A Physical And Psychological Lens, Meagan Munley, Carrie Flickinger

Fall Showcase for Research and Creative Inquiry

We will investigate the physical impacts both short and long term effects of of substance use. In doing so we will frame an argument for the substance's addictive properties as it relates to both its physically addictive and sociological addictive properties. In doing, so a stronger understanding of how an individual can move through the stages of substance use, to abuse, and finally addiction will be reviewed. We will then address current treatment strategies for the substance and how they address or fail to address both the physical and sociological impacts of its use.


So, You Want To Take Zoloft (Sertraline)?: A Biological & Psychological Analysis, Hailey Lux, Mackenzie Harry Nov 2021

So, You Want To Take Zoloft (Sertraline)?: A Biological & Psychological Analysis, Hailey Lux, Mackenzie Harry

Fall Showcase for Research and Creative Inquiry

A lot of individuals around the world suffer with panic disorders, post-traumatic stress disorder (PTSD), obsessive compulsive disorder (OCD). One drug that has been found to significantly decrease these feelings of stress is Sertraline. Sertraline has been proven to increase quality of life among individuals with certain mental health disorders. In addition, it is commonly known as Zoloft and is prescribed to individuals by doctors and psychiatrist. However, we will be talking about how in extreme causes sertraline could become addictive and have withdrawal side effects. Furthermore, during this poster presentation we will be discussing how sertraline is not an …


Statistical Potentials For Rna-Protein Interactions Optimized By Cma-Es, Takayuki Kimura, Nobuaki Yasuo, Masakazu Sekijima, Brooke Lustig Oct 2021

Statistical Potentials For Rna-Protein Interactions Optimized By Cma-Es, Takayuki Kimura, Nobuaki Yasuo, Masakazu Sekijima, Brooke Lustig

Faculty Research, Scholarly, and Creative Activity

Characterizing RNA-protein interactions remains an important endeavor, complicated by the difficulty in obtaining the relevant structures. Evaluating model structures via statistical potentials is in principle straight-forward and effective. However, given the relatively small size of the existing learning set of RNA-protein complexes optimization of such potentials continues to be problematic. Notably, interaction-based statistical potentials have problems in addressing large RNA-protein complexes. In this study, we adopted a novel strategy with covariance matrix adaptation (CMA-ES) to calculate statistical potentials, successfully identifying native docking poses.


3d-Printable And Open-Source Modular Smartphone Visible Spectrophotometer, Brandon Winters, Nick Banfield, Cassandra Dixon, Anna Swensen, Dakota Holman, Braxton Fillbrown Oct 2021

3d-Printable And Open-Source Modular Smartphone Visible Spectrophotometer, Brandon Winters, Nick Banfield, Cassandra Dixon, Anna Swensen, Dakota Holman, Braxton Fillbrown

Chemistry Faculty Publications

The past four decades have brought significant and increasingly rapid changes to the world of instrument design, fabrication, and availability due to the emergence of 3D printing, open-source code and equipment, and low-cost electronics. These, along with other technological advances represent a nexus in time ripe for the wide-spread production and availability of low-cost sophisticated scientific equipment. To that end, the design of a 3D printable and open-source, modular spectrometer is described. This specific instrument is distinctly different from others that have been reported in recent years in that it was designed outside of the “black box” paradigm of …


Physical Chemistry, Ruth E. Stark Oct 2021

Physical Chemistry, Ruth E. Stark

Open Educational Resources

This is a provisional syllabus for Physical Chemistry I (Thermodynamics), to be taught using an OER Textmap in Fall, 2021.


Correlation Effects On Intramolecular C-H...Oh And O-H...O Hydrogen Bond Interactions In Azelaic Acid: An Ab Initio Study, Sabina Kalata, Alina Huang, Ruben Parra Aug 2021

Correlation Effects On Intramolecular C-H...Oh And O-H...O Hydrogen Bond Interactions In Azelaic Acid: An Ab Initio Study, Sabina Kalata, Alina Huang, Ruben Parra

DePaul Discoveries

Electron correlation effects on both conventional, O-H…O, and nonconventional, C-H…O, intramolecular hydrogen bonds present in a selected azelaic acid folded conformation were evaluated ab initio using HF and MP2 methodologies. The relative strength of the hydrogen bonds was examined through different indicators derived from geometry, vibrational frequencies, and electron density along the hydrogen bond path. The HF method results in weaker O-H…O and C-H…O hydrogen bonds when compared with the corresponding results using the MP2 method. Additionally, the stability of the folded azelaic conformation is found to depend on the level of theory used. Accordingly, the zero-point corrected energies of …


The Role Of Hydrogen Bonding And Hydrogen Migration In Different Environments, Nassim Beiranvand Aug 2021

The Role Of Hydrogen Bonding And Hydrogen Migration In Different Environments, Nassim Beiranvand

Chemistry Theses and Dissertations

Hydrogen bonding is one of the most important topics in chemistry and has been a subject of many studies for years, using both experimental techniques and computational methods. My dissertation focuses on mechanistic studies of various types of intermolecu-lar and intramolecular hydrogen bonding in di˙erent systems based on quantum chemical calculations. In my work, I investigated the interplay of ring puckering and hydrogen bonding in DNA building blocks; hydrogen bonding in natural and unnatural base pairs and the nature of dihydrogen bonding by applying the Ring Puckering Analysis and the Local Vibrational Mode Theory (LVM). An additional aim of my …


From Small Molecules To Infinite Crystals: Probing Noncovalent Interactions Through Vibrational Spectroscopy, Sadisha Nanayakkara Aug 2021

From Small Molecules To Infinite Crystals: Probing Noncovalent Interactions Through Vibrational Spectroscopy, Sadisha Nanayakkara

Chemistry Theses and Dissertations

During my four years in the CATCO group supervised by Dr. Kraka, I have been exposed to various topics targeted to address a multitude of chemical problems, broadening our knowledge of modern chemistry research as we know it. In undertaking the age-old problem of understanding the nature of chemical bonding, I could modestly contribute with my work, using in-house tools based on vibrational spectroscopy.

First part of my dissertation is focused on inventing new methods and tools to efficiently investigate chemical bonding, followed by the study of some non-covalent interactions, imperative in catalysis and solid-state chemistry. This includes analysis of …


Quantum Chemical Investigation Of Novel Noncovalent Interactions Utilizing Vibrational Spectroscopy, Seth Francis Yannacone Aug 2021

Quantum Chemical Investigation Of Novel Noncovalent Interactions Utilizing Vibrational Spectroscopy, Seth Francis Yannacone

Chemistry Theses and Dissertations

Theoretical/computational methods have been utilized to investigate a diverse array of questions currently at the forefront of modern chemistry research. The focus of this work is Local Vibrational Mode (LVM) Theory, originally formulated by Konkoli and Cremer, and under continuous development by the CaTcO research group. Derived from LVM theory, local stretching force constants (ka) represent physically meaningful measurements of chem- ical bond strength. Decomposition of normal vibrational modes into LVM contributions, also called characterization of normal modes (CNM), is another powerful manifestation of LVM theory; most notably when applied to the analysis of theoretical/experimental IR/Ra- man spectra. Recent developments …


Identification Of Chemical Structures And Substructures Via Deep Q-Learning And Supervised Learning Of Ftir Spectra, Joshua D. Ellis Aug 2021

Identification Of Chemical Structures And Substructures Via Deep Q-Learning And Supervised Learning Of Ftir Spectra, Joshua D. Ellis

MSU Graduate Theses

Fourier-transform infrared (FTIR) spectra of organic compounds can be used to compare and identify compounds. A mid-FTIR spectrum gives absorbance values of a compound over the 400-4000 cm-1 range. Spectral matching is the process of comparing the spectral signature of two or more compounds and returning a value for the similarity of the compounds based on how closely their spectra match. This process is commonly used to identify an unknown compound by searching for its spectrum’s closes match in a database of known spectra. A major limitation of this process is that it can only be used to identify …


Ahr Expression On Rorc-Expressing Immune Cells Is Essential For I3c-Mediated Protection Against Colitis, Michal C. Williams Jul 2021

Ahr Expression On Rorc-Expressing Immune Cells Is Essential For I3c-Mediated Protection Against Colitis, Michal C. Williams

Senior Theses

Colitis is an inflammatory bowel disorder (IBD) whose etiology is attributed to modification in the luminal microbiota and dysregulation in the immune response. Indole is a signaling molecule which is naturally produced by gut luminal microbiota. Indole-3- carbinol (I3C) is a compound commonly found in vegetables and a ligand for the aryl hydrocarbon receptor (AhR). Previous studies have detected decreased expression and activation on the AhR receptor in colitis patients, thought to possibly alter gut microbiota metabolism, subsequently promoting colitis. 1 AhR, expressed in a variety of immune and epithelial cells, contributes to gut homeostasis by affecting vital mediators such …


Structure And Reactivity Of The First Row Transition Metals Bearing Redox-Active Ligands And Tunable H-Bonding Interactions, Khashayar Rajabimoghadam Jul 2021

Structure And Reactivity Of The First Row Transition Metals Bearing Redox-Active Ligands And Tunable H-Bonding Interactions, Khashayar Rajabimoghadam

Chemistry Theses and Dissertations

Metalloenzymes, as natural catalysts, can break a reaction with high activation energy to multiple small reactions with lower activation energies; in these small reactions, multiple bonds form and dissociate rapidly, some metalloenzymes use redox-active ligands in their active site to provide the needed electrons for these multiple small reactions. Additionally, in the secondary coordination sphere in the vicinity of the metalloenzymes, the hydrogen bonding interactions facilitate the transfer and interaction of the substrates and the stabilization of the active intermediates. These unique features in metalloenzymes inspired chemists to design molecular models that can partially mimic the structure and reactivity of …


The Coordination Chemistry Of The Rhodizonate Dianion And Its Decomposition Products, Joshua A. Silverman Jun 2021

The Coordination Chemistry Of The Rhodizonate Dianion And Its Decomposition Products, Joshua A. Silverman

FIU Electronic Theses and Dissertations

The rhodizonate dianion is of importance for forensic testing, specifically with regard to the sodium rhodizonate test for lead in gunpowder residues. In an effort to understand this test from a chemical perspective, the coordination of rhodizonate and its decomposition products, croconate and oxalate, with several metals has been investigated with a variety of structural and spectroscopic methods.

FT-IR data of the three sequential steps of the sodium rhodizonate test show coordination between Pb(II) atoms, tartrate anions, and rhodizonate dianions, with the tartrate being substituted for Cl- once a 5% HCl solution is added to produce the confirmatory blue-purple …


Lanthanide Interactions With Ligands And Biomolecules: Spectroscopic And Extraction Studies, Setareh Sakhdari Jun 2021

Lanthanide Interactions With Ligands And Biomolecules: Spectroscopic And Extraction Studies, Setareh Sakhdari

FIU Electronic Theses and Dissertations

Lanthanides (Ln), also known as rare earth metals, have been utilized for industrial and biological purposes and are commonly encountered in the 3+ oxidation state as Ln3+. The presence of Ln in spent nuclear fuel introduces problems during the transmutation and partitioning of actinides (An) due to the Ln high neutron cross-sections. Therefore, designing ligands for Ln3+ complexation, can be helpful for their separation from An3+ in nuclear technology. Also, the biomimetic roles of Ln3+ could be suitable for studying the biological macromolecules, such as the Ca2+-binding EF-hand proteins that are otherwise inaccessible …


Emergent Photophysics In Diketopyrrolopyrrole Superstructures, Andrew Levine Jun 2021

Emergent Photophysics In Diketopyrrolopyrrole Superstructures, Andrew Levine

Dissertations, Theses, and Capstone Projects

Organic semiconductors have received substantial attention as active components in optoelectronic devices because of their processability and customizable electronic properties. Tailoring the organic active layer in these devices to exhibit desirable optoelectronic properties requires understanding the complex and often subtle structure-property relationships governing their photophysical response to light. Both structural organization and frontier molecular orbitals (FMO) play pivotal roles in energy relaxation processes, and complex interplay between organization and orbital energies are difficult to anticipate based upon the molecular structure of the components alone, especially in systems comprised of multiple components. In pursuit of design rules, there is a need …


Cu-Promoted C-H Bond Hydroxylation Inspired By Cu-Dependent Metalloenzymes, Rachel Trammell May 2021

Cu-Promoted C-H Bond Hydroxylation Inspired By Cu-Dependent Metalloenzymes, Rachel Trammell

Chemistry Theses and Dissertations

From 2003 to 2015, Schӧnecker and Baran proposed a dinuclear Cu/O2 species in their mechanistic proposal for the hydroxylation of sp3 C-H bonds within their systems (proposed based on yields). Inspired from the site selectivity of this methodology and poor analysis of the mechanism, the first project was inspired to re-examine the sp3 C-H bond hydroxylation by Schrӧnecker and Baran and perform an intensive investigation into understanding how Cu/O2 interact which led us to propose a new mechanism based on the evidence collected (i.e., LCuII-hydroperoxide species that undergoes homolytic O-O bond cleavage). From there …


Investigations Involving Mononuclear And Dinuclear Transition Metal Catalysts For Photochemical Carbon Dioxide Reduction, Ansu Edwards May 2021

Investigations Involving Mononuclear And Dinuclear Transition Metal Catalysts For Photochemical Carbon Dioxide Reduction, Ansu Edwards

Honors Theses

There is currently a global energy crisis, which is in desperate need of solutions. New energy sources are required that will not pollute as much as our longstanding reliance on nonrenewable fossil fuels as an energy source. This pollution involves large amounts of greenhouse gas emissions, predominantly carbon dioxide (CO2), that contribute to environmental problems such as climate change. In this context, a fairly recent research direction to address this problem is the development of transition metal catalysts that can convert CO2 into reduced carbon products that can serve as chemical fuels. This work focuses on the …


Applications Of Sodium Azide In The Synthesis Of Tetrazines And Hydrolysis Reactions, My Le May 2021

Applications Of Sodium Azide In The Synthesis Of Tetrazines And Hydrolysis Reactions, My Le

Honors Theses

The inverse electron demand Diels−Alder cycloadditions of heterocyclic azadienes have provided a robust methodology for synthesizing highly substituted and functionalized heterocycles. It is widely used in organic synthesis and the pharmaceutical industry in the divergent construction of screening libraries and bioorthogonal conjugation. Each heterocyclic azadiene was found to possess a unique reactivity toward different classes of dienophiles, display predictable modes of cycloaddition, and exhibit substantial substituent electronic effects impacting their intrinsic reactivity and cycloaddition regioselectivity. Synthesis of 1,2,4,5-tetrazine has been reported in the literature since the late 19th century, showing scientists' tremendous interest in its application.

Herein we attempt to …


Small Molecule Activation By Transition Metal Complexes: Studies With Quantum Mechanical And Machine Learning Methodologies, Justin Kyle Kirkland May 2021

Small Molecule Activation By Transition Metal Complexes: Studies With Quantum Mechanical And Machine Learning Methodologies, Justin Kyle Kirkland

Doctoral Dissertations

One of the largest areas of study in the fields of chemistry and engineering is that of activation of small molecules such as nitrogen, oxygen and methane. Herein we study the activation of such molecules by transition metal compounds using quantum mechanical methods in order to understand the complex chemistry behind these processes. By understanding these processes, we can design and propose novel catalytic species, and through the use of data-driven machine learning methods, we are able to accelerate materials discovery.


Synthesis Of A Dd-Π-Aa Organic Dye For Dye-Sensitized Solar Cells, Hope Lovell May 2021

Synthesis Of A Dd-Π-Aa Organic Dye For Dye-Sensitized Solar Cells, Hope Lovell

Honors Theses

This project investigates the synthesis of a DD-π-AA (dual donor/dual acceptor) organic dye as a potential sensitizer for dye-sensitized solar cells (DSCs). The design of this dye was based off previous research that found dual donor/dual acceptor dyes exhibited promising results when used in a DSC. The donor groups, acceptor groups, and π-bridge were chosen for their stability, ability to absorb in the near-infrared (NIR) region, and intramolecular charge transfer (ICT) abilities.

While many components of the dye were synthesized, the final stages of the synthetic scheme were not completed due to the loss of time from COVID-19. Had the …


A Project To Dye For : Differentiation Of Dyed And Non-Dyed Human Hairs Using Atr Ft-Ir Spectroscopy, Joseph John Greco May 2021

A Project To Dye For : Differentiation Of Dyed And Non-Dyed Human Hairs Using Atr Ft-Ir Spectroscopy, Joseph John Greco

Legacy Theses & Dissertations (2009 - 2024)

IR spectroscopy is widely utilized for forensic purposes due to the chemical fingerprint the method provides. ATR FT-IR spectroscopy is particularly advantageous because it allows for spectra to be collected quickly, accurately, and perhaps most importantly for forensics, non-destructively. Human hair is commonly collected at a crime scene, and further analyzed using DNA analysis and microscopy. However, these techniques have limitations. In the past ATR FT-IR spectroscopy has shown promise in the analysis of human hair for forensic purposes. In this study, the differentiation of undyed hair versus dyed hair classes of varying colors based on their IR spectra were …


Synthesis Of A Zinc Dipyrrin Complex For Photocatalytic Reduction Of Co2, Sylvia Meredith May 2021

Synthesis Of A Zinc Dipyrrin Complex For Photocatalytic Reduction Of Co2, Sylvia Meredith

Undergraduate Honors Theses

Zinc dipyrrin complexes have the potential to act as cheap, effective photosensitizers. Synthesizing and studying different types could lead to more efficient solar energy harvesting processes, especially the production of solar fuel. Here, two attempts to synthesize 1,3,7,9-tetraphenyl-5-mesityldipyrromethene are reported and discussed. According to 1H NMR, the first synthesis attempt was not successful. The second synthesis attempt was not purified effectively, so 1H NMR produced inconclusive results. Further purification strategies or alternate synthesis methods are required.


The Synthesis Of Photoswitchable Triptan Derivatives, Chelsea Sainsbury May 2021

The Synthesis Of Photoswitchable Triptan Derivatives, Chelsea Sainsbury

Honors College

Serotonin has various functions throughout the body and directly effects many neurological diseases/disorders, like depression, that are linked to the dysregulation of serotonin. Triptans are indole containing drugs that bind to a subset of serotonin receptors (5-HT1Band 5-HT1D) and are used to treat migraines. In this project, the synthesis of anindole intermediate is attempted. Ideally, an azobenzene would have been added to the 5th position (replacing the primary amine). Azobenzenes are compounds composed of 2 benzene rings connected by a nitrogen-nitrogen double bond that can switch between cis and trans conformations by absorbing different wavelengths of light. The transformation of …


Synthesis And Conductivity Analysis Of A Methyl (Polyethylene Glycol) Comb Polymer, Olivia Fox Apr 2021

Synthesis And Conductivity Analysis Of A Methyl (Polyethylene Glycol) Comb Polymer, Olivia Fox

Honors Theses

The overall goal of work in this field is to improve materials for use in a variety of applications in fuel cell and battery production. This thesis specifically investigates the synthesis of two variations of a methyl (polyethylene glycol) comb polymer electrolyte (MePEGnwhere n=7) to understand how the molecular structure of an ion-conducting polymer affects its electrochemical properties. The MePEG used in this synthesis contains seven ethylene glycol groups and was added to a poly (methylhydrosiloxane) comb polymer backbone. In the first sample, the polymer contained only the MePEG sidechain, and in the second sample, the polymer contained …