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Analysis Of Petroleum Products For Forensic And Environmental Applications, Sarah Ghali, Sarah Porter 2020 Longwood University

Analysis Of Petroleum Products For Forensic And Environmental Applications, Sarah Ghali, Sarah Porter

Student Showcase for Research and Creative Inquiry

In both forensic and environmental applications, it is often important to identify ignitable liquid (IL) residues, to find a suspect or to clean up an oil spill. The ASTM method is commonly used; the extraction methods vary, but the data collection is the same. The instrument used in the ASTM method is gas chromatography mass spectroscopy (GC-MS), which allows a visual identification of the IL contaminating the sample. In this study, the use of Fourier transform infrared spectrometry (FTIR) was used in conjunction with chemometric analysis. Samples were prepared were to simulate an oil spill in natural waters. Two chemometric ...


Analysis Of Phenolic Compounds In Moroccan Olive Oils By Hplc, Hannah Meyls, Sarah Porter 2020 Longwood University

Analysis Of Phenolic Compounds In Moroccan Olive Oils By Hplc, Hannah Meyls, Sarah Porter

Student Showcase for Research and Creative Inquiry

Five extra virgin olive oils collected from farms in Morocco were analyzed for phenolic compounds. To complement these data, the chemical composition of the olive oils were analyzed by high-performance liquid chromatography. Several phenolic compounds were identified and quantified in the olive oils. Specifically, levels of oleuropein and luteolin were quantified in the low mg/kg range, and qualitative comparisons were made between the oil samples for tyrosol, vanillic acid, and apigenin. To compare extraction efficiency of different extraction solvents, methanol and DMF were used.


The Effects Of Storage Conditions And Time On Extracted Ignitable Liquids, Sierra N. Strnisa, Stephanie J. Wetzel 2020 Duquesne University

The Effects Of Storage Conditions And Time On Extracted Ignitable Liquids, Sierra N. Strnisa, Stephanie J. Wetzel

Graduate Student Research Symposium

In arson investigation, the presence of ignitable liquid is important in determining intent. In some cases, extracts of fire debris recovered from the scene must be stored for later analysis; though little is known about how to properly store extracted samples while upholding analytical integrity over time. Three petroleum distillates were selected as samples and extracted onto activated charcoal strips using a passive headspace method. Samples were transferred to a nylon fire debris bag or PTFE-lined glass vial. Once contained, samples were stored at room temperature or refrigerated for 3, 6, and 9 months then analyzed using gas chromatography mass ...


Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, Alexandra Reddy 2020 Liberty University

Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, Alexandra Reddy

Senior Honors Theses

Aquatic organisms often mistake microplastic particulates (MP) as food and inadvertently ingest the particulates, which can biomagnify through the food chain. While MP ingestion is well-researched in the marine environment, little is known about microplastics in freshwater  ecosystems. This project explores MP occurrence in an ecologically significant freshwater invertebrate: crayfish. Crayfish from two Central Virginia streams are collected to identify MP in the digestive tracts and gill filaments, and characterize the MP using analytical chemistry techniques. It was determined that MP were present in the digestive tracts and gill filaments of crayfish collected from both streams, and that MP frequency ...


Crystallographic Facet Selective Her Catalysis: Exemplified In Fep And Nip2 Single Crystals, Bryan Owens-Baird, Juliana P.S. Sousa, Yasmine Ziouani, Dmitri Y. Petrovykh, Nikolai A. Zarkevich, Duane D. Johnson, Yury V. Kolen'ko, Kirill Kovnir 2020 Iowa State University and Ames Laboratory

Crystallographic Facet Selective Her Catalysis: Exemplified In Fep And Nip2 Single Crystals, Bryan Owens-Baird, Juliana P.S. Sousa, Yasmine Ziouani, Dmitri Y. Petrovykh, Nikolai A. Zarkevich, Duane D. Johnson, Yury V. Kolen'ko, Kirill Kovnir

Ames Laboratory Accepted Manuscripts

How the crystal structures of ordered transition-metal phosphide catalysts affect the hydrogen-evolution reaction (HER) is investigated by measuring the anisotropic catalytic activities of selected crystallographic facets on large (mm-sized) single crystals of iron-phosphide (FeP) and monoclinic nickel-diphosphide (m-NiP2). We find that different crystallographic facets exhibit distinct HER activities, in contrast to a commonly held assumption of severe surface restructuring during catalytic activity. Moreover, density-functional-theory-based computational studies show that the observed facet activity correlates well with the H-binding energy to P atoms on specific surface terminations. Direction dependent catalytic properties of two different phosphides with different transition metals, crystal structures, and ...


Synthesis Of Cyclopropyl Analogs Of Stereochemically Rigid Probes Of Certain Pharmacological Receptors, Douglas Armstrong, Zachary Emptage, Anderson Verhoeven 2020 Olivet Nazarene University

Synthesis Of Cyclopropyl Analogs Of Stereochemically Rigid Probes Of Certain Pharmacological Receptors, Douglas Armstrong, Zachary Emptage, Anderson Verhoeven

Scholar Week 2016 - present

Douglas Armstrong, lead ONU faculty researcher, and his two research students, Zachary Emptage and Anderson Verhoeven, expanded their previous research (centered around acetylcholine and cholinergic activity), to include other types of pharmacological receptors, but again, aiming at the same type of compounds (cyclopropyl) to confer conformational (stereochemical) rigidity. The focus now is on compounds which, like acetylcholine, also contain an oxygen atom and a nitrogen atom separated by two carbon atoms, but which have pharmacological activity other than cholinergic. Several pharmacological categories have this pattern as known medicinal agents (“drugs”), including certain antidepressants, antihistamines, anti-anxiety drugs, etc. For some, there ...


Inorganic Chemistry Faculty Value Student-Centered Learning, But Time Constraints And Student Evaluations Discourage Change, Jenna Savage, Hope Heideman 2020 Hope College

Inorganic Chemistry Faculty Value Student-Centered Learning, But Time Constraints And Student Evaluations Discourage Change, Jenna Savage, Hope Heideman

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

Improving student success in chemistry requires faculty change, but change is hard. The Interactive Online Network of Inorganic Chemists (IONiC) is a community of practice (CoP) that offers teaching resources for inorganic chemistry faculty. We are studying the ways in which CoPs can promote faculty change. IONiC is supporting twenty inorganic chemistry faculty in implementing effective teaching methods into their foundation-level inorganic chemistry courses. In order to better understand how faculty make decisions about teaching, these faculty were interviewed about their teaching beliefs, approaches, and dissatisfactions. The interview data were coded via thematic content analysis and have shown that inorganic ...


Computational Chemistry In The Cloud, Gregory Campbell 2020 Hope College

Computational Chemistry In The Cloud, Gregory Campbell

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

Computational chemistry requires expensive computers and significant computer expertise. We are remedying these issues by using cloud computing to lower costs and by developing our Server In The Cloud (SITC) script to reduce the need for local expertise. SITC implements computational chemistry engines with the user-friendly WebMO interface on Google and Amazon cloud computers. In this way, we are making computational chemistry cheaper and more accessible to a wider range of chemistry students and researchers.


Development Of Paper-Based Screen-Printed Carbon-Paste Electrode For Sensing Glucose For Diabetics, Yechan Hwang 2020 Hope College

Development Of Paper-Based Screen-Printed Carbon-Paste Electrode For Sensing Glucose For Diabetics, Yechan Hwang

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

In recent years there have been many interests in developing paper based electrodes.[1] The purpose of this project is to develop a working paper-based electrode that can detect glucose via an enzyme and redox mediator (Tris(5-amino-1, 10-phenanthroline) Iron(II)). In the process of developing a paper-based electrode, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used as primary methods. The redox mediator was electropolymerized onto glassy carbon (GC) and carbon-paste electrodes (CPE) and their subsequent charge-transfer properties were characterized using CV and EIS. Cyclic voltammetry characterization studies of the electropolymerized films revealed excellent charge transfer properties with ...


Rhodium-Catalyzed Carbon-Carbon Bond Activation Utilizing Removable Amide Directing Groups, Claire Muckian, Greg Hedrick, Jonathan Vanden Akker, Constance B. Anderson 2020 Hope College

Rhodium-Catalyzed Carbon-Carbon Bond Activation Utilizing Removable Amide Directing Groups, Claire Muckian, Greg Hedrick, Jonathan Vanden Akker, Constance B. Anderson

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

Carbon-carbon bonds are known for their relative stability. Past research has shown that certain metal catalysts are capable of breaking carbon-carbon bonds when a chelating directing group is present in the molecule. Methods involved in carbon-carbon bond activation could be greatly expanded through the use of removable directing groups.

This work employs amides as removable directing groups. These rhodium-catalyzed reactions involve successful C–C bond activation of the amides followed by coupling with a variety of substrates including Michael acceptors, alkenes, and boronic acids. Ongoing studies are required to optimize the reaction, to explore the substrate scope, and to determine ...


Mechanistic Survey Of Rhodium-Catalyzed Decarbonylation Reactions: A Kinetics Study, Julia Loula, Erik Schoonover 2020 Hope College

Mechanistic Survey Of Rhodium-Catalyzed Decarbonylation Reactions: A Kinetics Study, Julia Loula, Erik Schoonover

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

The kinetics involved in the reaction pathways of transition metal-catalyzed carbon-carbon bond activation reactions can provide key insights into the mechanism. Previous work has shown that pyridyl ketones undergo rhodium-catalyzed decarbonylation reactions. The determination of the mechanistic pathway of this reaction could allow for the knowledge necessary for exploring alternative reactivity. Utilizing in situ Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance Spectroscopy (NMR), kinetic analysis of the decarbonylation reaction is being performed with various substituted pyridyl ketones. Initial rate constants will be used to compare the electronic effects of substituents, providing insight of the intermediates involved.


Computational Chemistry - Ulk 101, Michaela Montpas 2020 Olivet Nazarene University

Computational Chemistry - Ulk 101, Michaela Montpas

Scholar Week 2016 - present

Autophagy is a process that generates the necessary building components for cells by cytoplasmic breakdown of unnecessary materials (Martin, Celano, Solitro, Gunaydin, Scott, et. al., 2018). This is a survival technique for cells in times of stress, especially during periods of nutrient starvation. Cancer cells, unfortunately, benefit from this process due to their ability to flourish in nutrient-starved environments, becoming resistant to therapy. The primary protein in mammals responsible for this process is a serine/threonine kinase called ULK 1 (unc-51 like autophagy initiating kinase 1). As such, inhibitors of ULK 1 can be used in cancer therapies in order ...


Research And Review Of Polymethyl-Methacrylate Copolymers In The Development Of Enhanced Pharmaceutical Delivery Systems, Jake Dyess 2020 Liberty University

Research And Review Of Polymethyl-Methacrylate Copolymers In The Development Of Enhanced Pharmaceutical Delivery Systems, Jake Dyess

Senior Honors Theses

The following thesis shall primarily explore the current research regarding the implementation of modifiable microscopic and nanoscopic polymer particles as novel pharmaceutical delivery systems. Polymethacrylate-based copolymers, such as EudragitTM, are sensitive to alterations in pH levels, becoming increasingly more soluble in response to an increase in pH. The selective solubility and modifiable nature of these polymers allows for greater flexibility of treatment options for patients (Patra et al., 2017). The wide range of functionality of polymethacrylate (PMA) may provide solutions to challenges relating to the current treatment and therapy of certain conditions. Research indicates that PMA based micro- and ...


Phosphorus Nmr And Its Application To Metabolomics, Paula Evans, Fatema Bhinderwala, Robert Powers, Martha Morton, Thomas Smith 2020 University of Nebraska - Lincoln

Phosphorus Nmr And Its Application To Metabolomics, Paula Evans, Fatema Bhinderwala, Robert Powers, Martha Morton, Thomas Smith

UCARE Research Products

Stable isotopes are routinely employed by NMR metabolomics to highlight specific metabolic processes and to monitor pathway flux. 13C-carbon and 15N-nitrogen labeled nutrients are convenient sources of isotope tracers and are commonly added as supplements to a variety of biological systems ranging from cell cultures to animal models. Unlike 13C and 15N, 31P-phosphourous is a naturally abundant and NMR active isotope that doesn’t require an external supplemental source. To date, 31P NMR has seen limited usage in metabolomics because of a lack of reference spectra, difficulties in sample preparation, and an absence of two-dimensional (2D) NMR experiments. But, 31P ...


An Experiential Report On The Thayer Method Of Teaching Across College-Level Chemistry, Biology, Math, And Physics Courses, Kevin P. O'Halloran, Sairam Tangirala, Fengjie Sun, Leonard E. Anagho, Gerald Agbegha, Clay Runck, David Roth, Amy H. Erickson 2020 Georgia Gwinnett College

An Experiential Report On The Thayer Method Of Teaching Across College-Level Chemistry, Biology, Math, And Physics Courses, Kevin P. O'Halloran, Sairam Tangirala, Fengjie Sun, Leonard E. Anagho, Gerald Agbegha, Clay Runck, David Roth, Amy H. Erickson

Georgia Journal of Science

The Thayer method of instruction is a little-known active learning technique that dates back to 1817 at the U.S. Military Academy. This study describes the implementation and statistical evaluation of an adaptation of the Thayer method in a variety of college science and math courses. All courses had five characteristics in common: (i) students were given a daily reading schedule and instructed to prepare before class, (ii) each class started with a question and answer session, (iii) class time minimized the use of lecture, (iv) class time maximized the use of active learning, and (v) students were frequently quizzed ...


The Influence Of Radiolytically Produced Nitric Acid On The Corrosion Resistance Of Copper-Coated Used Nuclear Fuel Containers, Joseph P. Turnbull 2020 The University of Western Ontario

The Influence Of Radiolytically Produced Nitric Acid On The Corrosion Resistance Of Copper-Coated Used Nuclear Fuel Containers, Joseph P. Turnbull

Electronic Thesis and Dissertation Repository

In Canada, the proposed disposal method for high level nuclear waste involves sealing the waste in steel containers with a 3 mm outer copper coating and burying it in a deep geologic repository. However, the thickness of the container is significantly reduced making a reassessment of the influence of γ-radiation, emitted by the waste form, on container corrosion a potential licensing requirement. Under humid aerated conditions, the formation of nitric acid is expected, potentially resulting in the formation of droplets or wetted layers on the container surface. Currently available literature on the corrosion of copper in nitric acid does not ...


Identification Of Histone H4-Based Peptoids As Inhibitors Of Prmt1, Megan DeMart, Molly Dubose, Sarah Mann, Corey Causey Ph.D. 2020 University of North Florida

Identification Of Histone H4-Based Peptoids As Inhibitors Of Prmt1, Megan Demart, Molly Dubose, Sarah Mann, Corey Causey Ph.D.

Showcase of Osprey Advancements in Research and Scholarship (SOARS)

Protein Arginine Methyltransferases (PRMTs) are a family of 11 mammalian enzymes characterized by the post-translational methylation of arginine residues in the histone tail. The majority of the 11 members of the PRMT family are divided into two main types, Type I and Type II. PRMT1, the major Type I isozyme, catalyzes the formation of asymmetrically dimethylated arginine (ADMA). PRMT1 activates transcription of cancer genes. Peptoids, or poly-N-substituted glycine’s are a class of oligomers whose side chains are appended to the nitrogen atom of the peptide backbone rather than the alpha carbon. Kinetic parameters were conducted for both peptide and ...


Investigating The Substrate Specificity Of Prmt1 Using A Plate Based Screening Method, Tina Sawatzky, Sarah Mann 2020 University of North Florida

Investigating The Substrate Specificity Of Prmt1 Using A Plate Based Screening Method, Tina Sawatzky, Sarah Mann

Showcase of Osprey Advancements in Research and Scholarship (SOARS)

Enzymes are biological catalysts that speed up the rate of a reaction by lowering the activation energy and converting substrate (reactant) to product more expeditiously. Enzymes have a high degree of specificity and will only catalyze selective reactions by targeting particular substrates. In mammals, there exists a family of 11 enzymes, PRMT’s (Protein Arginine Methyl transferase), that target protein arginine for post translational methylation on the guanidino nitrogen of the residue. They occur naturally as Type I, II and III and can administer asymmetric di-methylation (ADMA), symmetric dimethylation (SDMA) and monomethylation, respectively. The focal point of this project is ...


Fixing Mobile Desert Sands: Definition Of Water Resistance, Mechanical Strength And Mechanism Of Fixing, Shakhnoza Kuldasheva, I. L. Ahmadjonov, N. Z. Adizova, I. D. Eshmetov, Kh. I. Akbarov 2020 Institute of General and Inorganic Chemistry, Uzbekistan Academy of Sciences

Fixing Mobile Desert Sands: Definition Of Water Resistance, Mechanical Strength And Mechanism Of Fixing, Shakhnoza Kuldasheva, I. L. Ahmadjonov, N. Z. Adizova, I. D. Eshmetov, Kh. I. Akbarov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

The possibility of the formation of a water-resistant structures in dispersions of saline soils by using a composition of additives combining a surfactant and a fixing agent, generally providing the effect of dispersed hardening, is considered. The data by investigation of method of fixing the sands of the Surkhandarya region with complex additives obtained on the basis of the waste of the Kungrad soda plant are presented. It is shown that the basis of the proposed method of fixing saline soils with complex additives is the process of converting their surface layers (up to 5 cm) from free-dispersed state to ...


Flux Growth Of Phosphide And Arsenide Crystals, Jian Wang, Philip Yox, Kirill Kovnir 2020 Wichita State University

Flux Growth Of Phosphide And Arsenide Crystals, Jian Wang, Philip Yox, Kirill Kovnir

Ames Laboratory Accepted Manuscripts

Flux crystal growth has been widely applied to explore new phases and grow crystals of emerging materials. To accommodate the needs of high-quality single crystals, the flux crystal growth should be reliable, controllable, and predictable. The selections of suitable flux and growth conditions remain empirical due to the lack of systematic investigation especially for reactions, which involve highly volatile components, such as P and As. Considering the flux elements, often the system in question is a quaternary or a higher multinary system, which drastically increases complexity. In this manuscript, on the examples of flux growth of phosphides and arsenides, guidelines ...


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