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Releases Of Hazardous Materials And Waste From Transportation Incidents In The Us: An Analysis To Increase Environmental Resiliency, Elizabeth Irene Tautges

Master's Projects and Capstones

Excessive amounts of hazardous materials and waste are released into the environment from transportation incidents. The United States federal government has regulations on the movement of hazardous material and waste during transportation, but preventing environmental releases is not a major priority. Multiple external factors influence the release of hazardous material and waste into the environment. Transportation incidents can be prevented by modifying the information collected in emergency reports, adjusting transportation patterns and conditions, and expressing negative environmental impacts, preparing responder efforts to communicate effectively. The components of previous hazardous materials and waste releases emphasize the needed improvements for increasing environmental …

Analysis Of The Effect Of Different Surface Preparation Methods On Corrosion Resistance And Adhesion Strength Of Astm A36 Steel Substrate With Surface Tolerant Epoxy Paint As Coating Material, Irwan Wijaya Santoso, Daffa Aqila, Rini Riastuti, Rizal Tresna Ramadhani

Journal of Materials Exploration and Findings

In the industrial world, to extend the service life of materials, protection methods are carried out to slow down the material's corrosion rate. The protection method that is often used is the coating method. The coating method is a protection method by coating the substrate material using a coating material to prevent contact between the substrate material and the environment. In this research, the substrate material used is ASTM A36 steel and the coating material used is Surface Tolerant Epoxy paint. The independent variable used in this study lies in the surface preparation method which consists of: solvent cleaning, hand …

Effects Of Ti Addition On The Characteristics Of Al-10zn-6mg-2si/Zro2 Composites Produced By Squeeze Casting, Qesha Diva Prameshvara, Pipin Indah Lestari, Bondan Tiara Sofyan

Journal of Materials Exploration and Findings

Metal matrix composite (MMC) with 7xxx aluminum matrix is potential for ballistic applications due to the combination of strength, toughness, and light weight. Previous study successfully produced aluminum-based composites with SiC particles which were able to stop type III bullet, however cracks remained on back of the plate. Therefore, in this research, SiC was replaced by zirconia (ZrO₂) due to its high fracture toughness. Ti-B grain refiner was added to further improve toughness through grain boundary strengthening mechanism. This research developed 5 vol.% ZrO₂ strengthened Al-10Zn-6Mg-2Si composite with addition of Al-5Ti-1B grain refiner produced through squeeze casting …

Comparison Of Various Theoretical Measures Of Aromaticity Within Monosubstituted Benzene, Caleb K. Swain, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The effects of monosubstitution on the aromaticity of benzene are assessed using a number of different quantitative schemes. The ability of the mobile π-electrons to respond to an external magnetic field is evaluated using several variants of the NICS scheme which calculate the shielding of points along the axis perpendicular to the molecule. Another class of measures is related to the drive toward the uniformity of C-C bond lengths and strengths. Several energetic quantities are devised to approximate an aromatic stabilization energy and the tendency of the molecule to maintain planarity. There is a lack of consistency in that the …

Advancing Coupled Cluster Methods: Tensor Factorization And Analytic Gradient Implementation, Tingting Zhao

Chemistry Theses and Dissertations

With the rapid advancement of computing capabilities, computational chemistry has become increasingly indispensable in both experiment design and the interpretation of experimental outcomes. Wave-function-based quantum mechanistic methods are highly sought after for their ability to provide high-accuracy data and their potential for systematic improvement. However, to extend their applicability to larger molecules, it is essential to employ rank-reducing approximations to these methods. This dissertation dedicates Chapters Three and Four to the development of rank-reduced methodologies. Additionally, beyond single-point energies, molecular geometries and properties of molecule-excited states hold paramount importance across diverse fields of chemistry. Hence, Chapter Five presents the work …

Towards Carbon Dioxide Reduction: Synthesis And Characterization Of Ccc-Nhc Pincer Iron Complexes., Joshua Mensah

Theses and Dissertations

The industrial revolution came with its downside of emission of greenhouse gases into the atmosphere. The NOAA reported in 2019 that, of the greenhouse gases emitted into the atmosphere, CO2 contributed to about 80% of the increased greenhouse gases hence the need for CO2 Sequestering and Storage (CSS) and ultimately leading to Carbon Capture and Recycling (CCR) as a viable option to convert CO2 into useful forms. The race to find the best catalyst for CCR has led to the synthesis of many organometallic compounds. Pincer complexes catalyzed CO2 reduction has gained notoriety recently because of the tunability and robustness …

Removal Of Phenol From Oilfield Produced Water Using Non-Conventional Adsorbent Medium By An Eco-Friendly Approach, Salem Jawad Alhamd, Mohammed Nsaif Abbas, Hassan Jameel Jawad Al-Fatlawy, Thekra Atta Ibrahim, Zaid Nsaif Abbas

Karbala International Journal of Modern Science

Petroleum extraction generates substantial quantities of produced water, a challenge compounded by water scarcity in oil-producing regions, notably the Middle East. Leveraging produced water effectively, adhering to environmental standards, can offer a viable solution to the issue of water scarcity. This study explores the potential of mandarin peels as an available, cost-effective adsorbent for treating synthetic aqueous solution simulated to oil-field produced water, specifically targeting phenol, a dangerous pollutant. Employing a batch-mode adsorption unit, six operational factors—phenol concentration, acidity, agitation speed, contact time, adsorbent dose, and temperature—were investigated. Results revealed an inverse relationship between phenol removal and pH, concentration, and …

The Effect Of Metabolic Modulators On The Rate Of Steady State Water Exchange In S. Cerevisiae Grown In Chemostat Bioreactors, Samantha Mumford, Mark Woods, Johnathan Dutra

Student Research Symposium

Water transport across the lipid bilayer due to osmotic stress causes a change in intracellular volume over time. At isotonic equilibrium there is no change in cell volume and yet water exchange does not stop. Water molecules continue to exchange rapidly with those of the extracellular space. The rate constant for steady state water efflux (k_io) can be measured using contrast enhanced magnetic resonance (MR) and the two-site exchange (2SX) model. k_io is known to correlate with the cellular energy molecule ATP making it a probable biomarker for metabolic diseases such as cancer. Measurements of k …

Competing Supramolecular Forces: Boron Coordination Vs Π-Π Stacking, Sidhaesh A. Agarwal, Gonzalo Campillo-Alvarado, Nicholas Lutz, Jesus Daniel Loya, Eric W. Reinheimer

Student Research Symposium

This study explores the impact of fluorination levels in azopyridine Lewis bases on their ability to direct the formation of B←N coordination adducts or cocrystals with phenylboronic ester. We hypothesize that the degree of fluorination can be used as a tool to control the outcome of supramolecular bonding competition, thus influencing complex self-assembly.

A series of azopyridines with varying degrees of fluorination were synthesized and reacted with phenylboronic ester. Their structures were analyzed using Hartree-Fock calculations, Hirshfeld surface analyses, and single crystal X-ray diffraction to assess the impact of fluorination on supramolecular interactions.

The study reveals that azopyridines with up …

Multiscale Variability Of Heavy Metals In A Western U.S. Snowpack, Kelsey Hefner

Student Research Symposium

Natural and anthropogenically sourced particulates are deposited from the atmosphere to landscapes via dry and wet deposition, making frozen winter snowpack a natural archive of atmospheric elemental composition. Wildfires in the Western United States are increasing in extent, duration, and severity, especially in alpine regions. Severe fires remove forest canopy and can impact how atmospheric elements are dispersed and stored across snow-dominated watersheds. We evaluated Al, V, Cr, Mn, Ni, Cu, As, Zn, Se, Mo, Cd, and Pb concentrations in 394 winter snow core samples. We collected samples in 2019 and 2020 from a chronosequence of eight forests that burned …

Computationally Assisted Mechanistic Analysis Of The Protonolysis Of A Pt–Me Bond, Clement Dasilva

Student Research Symposium

Mechanistic study of the protonolysis of (cod)PtMe2 could give insight into the activation of C-H bonds by platinum because it is the microscopic reverse reaction. Two possible mechanisms for the protonolysis of dimethyl platinum complexes have been proposed, with experimental and computational data supporting the single step, SE2, over the multistep, SE(ox) mechanism. New experimental work from our group supports a multi-step mechanism with multiple acid molecules. In this work, the SE2 mechanism as well as a proposed SE(ox) mechanism were computationally modeled with a single equivalent of acid, TFAH, and two equivalents using density functional theory. The modeled pathways …

Method Validation Of Metals In Environmental Soil Samples, Sofia Deangelis, Nana Nguyen

Student Research Symposium

Vehicles are a major source of metal accumulation in terrestrial environments. Green infrastructure, such as bioswales, has been implemented as a way to mitigate this damage. However, there is a limited understanding of the processes that occur in these bioswales as few go back after implementation to identify areas in the bioswale with accumulation of pollutants. Inductively coupled mass spectrometry (ICP-MS) has the potential to be used in this type of study due to the machine’s high sensitivity and selectivity. However complications can arise while using the ICP-MS to characterize complex environmental samples. This study seeks to optimize microwave assisted …

Photocathodes From Aerobic Oxidation Of Tellurorhodamines, Amelia Jellison

Student Research Symposium

Contemporary dye-sensitized solar cells are far less efficient than silicon solar panels, therefore this project seeks to develop an improved dye sensitized photocathode. Tellurorhodamine dyes, including mesityl derivatives and tellurium black, have been chosen to increase efficiency through increased light harvesting. The photophysical and electrochemical properties of tellurorhodamines with varying structures are analyzed to quantify its efficiency to serve as a dye sensitized photo cathode. Dyes undergo aerobic oxidation facilitated by light, the absorption profile is obtained before and after. Mesityl derivatives are known to experience significant red-shifting following aerobic oxidation. At its base oxidation state, tellurium black experiences an …

Exploring The Potential Of Α-Aryl Substitution Of Gddota To Address Challenges Associated With Mri Contrast Agents., Charlene I. Kupara

Student Research Symposium

Gadolinium chelates have found widespread application as contrast agents in Magnetic Resonance Imaging (MRI) a cornerstone in modern medical diagnostics. In recent years two significant challenges have emerged to the use of Gd³⁺ chelates in MRI:

• The safety of these Gd³⁺-based agents, specifically related to the possible in vivo release of Gd³⁺.
• The environmental impact of anthropogenic Gd³⁺ pollution of surface waters arising from using contrast agents.

The escalating reports of Gd³⁺ presence in environmental matrices, and its adverse effects on marine life and human health, necessitate urgent intervention to mitigate consequential environmental …

Model Of The Effect Of Voltage On Contact Angle In An Electrolytic Cell Reaction, Aaron Essilfie

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

This paper investigates the hypothesis that the contact angle at the meniscus of an electrode-electrolyte can be altered during a redox reaction through the coupled understanding of electrowetting and capillarity rise. Recent studies in electrowetting have focused on dielectric surfaces but research on contact angle at the electrode-electrolyte surface is lacking. The study employs a basic electrolytic cell. By applying principles of electrowetting and capillary rise the research aims to understand the relationship between applied voltage and contact angle, to advancements in electrochemistry and microfluidics.

An Overview Of How To Measure The Kinetic Properties Of An Anode Material For The Chlorine Evolution Reaction, Cameron Vann

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The process of generating chlorine gas using electrolysis in aqueous systems is well established. However, a new process requires chlorine to be generated at high temperatures using molten salt. This harsh environment requires a new study of anode materials for the chlorine evolution reaction. Anode materials can be compared by their kinetic parameters, the transfer coefficient α and the exchange current i0. The basic theory of these properties as they relate to the chlorine evolution reaction has been detailed and an analysis method for finding these effective parameters has been shown and demonstrated.

Model To Demonstrate Effects Of Mass Transfer And Applied Current In An Electrolytic Cell, George Ankrah

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

This study investigates the relationship between applied current and resulting cell potential in an electrolytic system, considering the transport of electroactive species. By applying Michael Faraday's laws of electrolysis and the Nernst-Planck equation, the behavior of electroactive species in diffusion-controlled systems with and without stirring is modeled. The plots demonstrate how stirring enhances ion transport and establishes a stable Nernst diffusion layer, affecting the kinetics of electrochemical reactions. Understanding these dynamics is crucial for optimizing electrolysis processes.

Review Of Cyclic Voltammetry Measurements For Uranium In Flinak Molten Salt, Jackson Ivory

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

The electrochemical behavior of uranium FLiNaK molten salts is explored, focusing on cyclic voltammetry (CV) as a powerful tool for redox characterization and diffusion studies. Through a comprehensive review of recent research, the study highlights the significance of CV in understanding electrode kinetics, material compatibility, and process optimization in molten salt environments. The findings underscore the potential of FLiNaK molten salt reactors in advancing nuclear energy technologies, fuel processing, and waste management strategies. Collaborative interdisciplinary efforts are emphasized to address challenges and accelerate innovation in electrochemical methods for nuclear applications.

Probing The Surface Structure Of Ferrocene Modified Electrodes Using Cyclic Voltammetry, Rebekah S. Stanley

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Modifying electrodes imparts new electrochemical properties for use in various applications. To fully understand these electrochemical properties the structure of the modified surface needs to be characterized. Cyclic voltammetry (CV) offers a quick and simple way to determine if the surface structure has been homogeneously modified even at low surface concentrations. Nonideal responses in CV scans give insights to the microenvironments and structure of the monolayer surface that may be indistinguishable in other techniques. Peak fitting CV data, coupled with other surface techniques, can further characterize the contributions and nature of these microenvironments and aid in structural determination.

Toxic Chocolate: An Investigation Of Heavy Metal Concentrations In Chocolate Products, Meredith E. Hoff

Student Scholarship

Many news organizations and scientific journals have recently reported high concentrations of lead and cadmium in chocolate products. The consumption of lead, cadmium, and other toxic metals can lead to numerous health impacts and impair development in children.1,2 Previous studies have specifically focused on the quantification of lead and cadmium in mainstream chocolate products, neglecting small businesses and the quantification of other heavy metals. This study addresses this disparity by analyzing the concentrations of lead, cadmium, barium, strontium, thallium, and mercury in lesser-known chocolate products from Castronovo Chocolate, Meridian Cacao Co., and Lidl. Two ICP-OES instruments and a direct mercury …

Purification And Isolation Of Α-Chloro-Β-Lactone Precursor Molecules, Matthew Ellis

Honors Projects

This research investigates the synthesis of α-chloro-β-lactone molecules, focusing on the production, isolation, and purification of two precursor compounds from chloroacetic acid and substituted benzaldehydes. While multiple methods were explored, including EDC, DIC, and DCC catalysis, DCC proved to be most effective in producing higher yields. However, challenges in purification arose due to the formation of byproducts, particularly with DCC, prompting further investigation for efficient extraction and purification techniques. DCC, however, shows a promising route for α-chloro-β-lactone synthesis, despite purification complexities.

Phase Equilibria And Heat Capacities For Tetraarylphosphonium-Based Ionic Liquids, Allan Wilson

Honors Theses

Climate change is one of the most pressing issues facing humanity in the 21st century. A major contributing factor to this problem is the continued use of fossil-fuel based sources of energy. Concentrated solar power (CST) with thermal energy storage (TES) provides a potential opportunity to support this transition away from fossil fuels but suffers from high costs and extended downtimes. Current heat transfer fluids used in these processes often consist of a mixture of alkali metal nitrates with melting points above 200°C. For CST and TES to be viable, a thermally stable, low melting fluid is needed. Ionic liquids …

Using Student Interests To Explore Inclusion In Undergraduate Chemistry, Sonja Hoversten

CSB and SJU Distinguished Thesis

For students who are not chemistry majors, but who are on a career track requiring four chemistry courses, taking the final reactivity chemistry course (CHEM 251) for pre-health students can be daunting. For this reason, this research is focused on the CHEM 251 course at The College of Saint Benedict and Saint John’s University (CSBSJU) which is one of the four required chemistry courses for pre-medicine and some pre-physician assistant students, and all chemistry and biochemistry majors. Student perception of inclusion in the course increased through the implementation of group assignments including prompts for individual application of the material. The …

Investigation Of Lignin Solubilization Using Quantum Chemical Calculations In Constrained Media, Leo Sanzone

Arts & Sciences Undergraduate Showcase

Lignin is a common, yet complex polymer found in a majority of vascular plants. The polymer can easily be functionalized, and it is a readily available and renewable source of carbon-based material without a petrol source. There are various methods to allow for the dissolution of lignin, one of which involves the use of H₂O and CO₂ in supercritical conditions. This particular solution bends the normal solvation rules and allows for multiple instances of H-bonding interactions.

By using Density Functional theory, this study aims to identify the molecular interactions of guaiacol (the most basic fragment of lignin) …

Peace With Painful Memories, Mona Muzammil, Muzammil Arshad, Washain Muzammil

Chemistry Faculty Publications and Presentations

This Book helps you identify and heal from childhood emotional neglect so you can be more connected and emotionally present in your life.

Do you sometimes feel like you’re just going through the motions in life? Do you often act like you’re fine when you secretly feel lonely and disconnected? Perhaps you have a good life and yet somehow, it’s not enough to make you happy. Or perhaps you drink too much, eat too much, or risk too much to feel something good. If so, you are not alone and you may be suffering from emotional neglect.

Are you one …

Development Of An Enhanced Sampling Workflow To Accelerate Molecular Docking With Sparse Biophysical Information, Zachary Stichter

Masters Theses & Specialist Projects

Rapid docking of flexible biological macromolecules remains a significant open challenge in protein structure determination. While rigid docking is relatively simple with toolkits such as TagDock, a key obstacle to rapid flexible docking is the complexity and roughness of the free energy surface associated with protein conformational motion (often termed the many-minima problem), meaning conventional molecular dynamics methods do not effectively sample protein conformations near the interaction complex in accessible timescales. Methods such as metadynamics and replica exchange molecular dynamics exist to ameliorate this obstacle, yet these methods use nonphysical biases or random swaps to enhance sampling. In contrast, high …

Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza

Electronic Theses and Dissertations

Metal complexes of dipyrromethene (dipyrrins) used as sensitizers in photocatalysis offer a way to harness solar energy in chemical bonds to create new fuels. This offers the dual role of reducing fossil fuel dependence and atmospheric CO₂ levels. Traditionally, metal dipyrrin complexes are synthesized using substituted pyrroles, aldehydes, and transition metals. Indoles have a more expanded pi-electron system and their dipyrrin-type complex may exhibit visible light absorption, suggesting that they can act as photosensitizers for CO₂ reduction processes. A novel indoledipyrromethene was synthesized using unsubstituted indole and mesitaldehyde. The complex exhibits visible light absorption at 422 nm. Its …

Optimization Of Xrf Experimental Protocol For Bruker Picofox, Tyler Ashcraft

Undergraduate Honors Theses

The research performed was to improve the precision and accuracy of sample measurements made with the Bruker Picofox X-ray fluorescence spectrometer. The initial method of sample preparation using a 10 μL drop spotted onto an acrylic plate and then drying in an oven at 80˚C produced inconsistent results even when processing replicates or the same sample multiples times. Multiple experiments were conducted to determine the effects of different sample preparation conditions on the resulting accuracy. The conditions tested were drop size, plate composition, and drying temperature. For each experiment an internal standard (gallium) was used at concentrations similar to that …

Enabling More Efficient Solar Thermal Energy Production And Storage, Allan Wilson

Poster Presentations

Concentrated Solar Power (CSP) stores & transfers energy using a Thermal Energy Storage Fluid (EIA AEO 2022)

College Of Natural Sciences Newsletter, Spring 2024, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 2 New Faculty and New Club on Campus
Page 3 2024 URSCAD Awards
Page 4 Day of Scholars 2024
Page 5 SDSU's First Representation at the Association for Anatomy's 2024
Annual Conference
Page 6-7 2024 Honor's College Convocation
Page 8 Other Student Activities
Page 9 Faculty Awards
Page 10-11 Other News
Page 12 2024 Drone Day and American Association of Geographers Convention - Hawaii
Page 13 55th Annual Geography Convention
Page 14 2024 Stethoscope Ceremony
Page 15 Open PRAIRIE Data