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Development Of Granulated Adsorbent For Clean-Up Of Water Contaminated By Cesium, Esther Alorkpa 2019 East Tennessee State University

Development Of Granulated Adsorbent For Clean-Up Of Water Contaminated By Cesium, Esther Alorkpa

Electronic Theses and Dissertations

A study was conducted on sol-gel synthesis of an adsorbent (phosphotungstic acid embedded in silica gel, H-PTA/SiO­2) of radioactive cesium. A novelty of this work is covalent bonding of PTA to the surface of solid support that prevents leaching from the surface of the material. The sample was granulated with a binder, aluminium oxide (γ-Al2O3). Solid-state NMR and FT-IR spectroscopy were used to confirm the presence of Keggin units of PTA in the bound materials. Thermal analysis of H-PTA/SiO­2 - γ-Al2O3 (50 %) showed that the water content in the bound material ...


Quantitative Analysis Of Iron In Beer Using Cloud Point Extraction, Joshua Rempfer 2019 University of Lynchburg

Quantitative Analysis Of Iron In Beer Using Cloud Point Extraction, Joshua Rempfer

Student Scholar Showcase

Determination of Iron concentration in Apocalypse Ale beer using a preconcentration method coupled with UV-Vis spectroscopy. Samples will be cross checked with MP-AES to ensure precise and accurate results.


Elemental Analysis Of Legacy Sediments At College Lake, Amelia Dalton 2019 University of Lynchburg

Elemental Analysis Of Legacy Sediments At College Lake, Amelia Dalton

Student Scholar Showcase

College Lake is a large reservoir located on the campus of the University of Lynchburg. College Lake’s ecosystem has degraded over the years due to the buildup of sediment, nutrients, and raw sewage. Increased urbanization in the area has also most likely contributed to the contaminants present within the system. Because of flooding issues during the summer of 2018, Lynchburg CIty officials drained College Lake, which caused sediment to be released downstream. To better understand the transport of heavy metals in the sediments released from College Lake, sediment core samples were taken from College Lake, Hollins Mill Park, and ...


Mobilization Of Calcium Across Mineralized Tissues In Yellow Perch, Perca Flavescens, Taylor Bopp 2019 University of Lynchburg

Mobilization Of Calcium Across Mineralized Tissues In Yellow Perch, Perca Flavescens, Taylor Bopp

Student Scholar Showcase

Bones in many higher teleost fish, such as percids and centrarchids, lack osteocytes that function as both chemo- and mechano-sensors, and thus, are not actively involved in homeostasis of blood calcium level. Nonetheless, the vertebrae of yellow perch, Perca flavescens (P. flavescens), living in darker and low calcium (Ca) water, have demonstrated adaptive modeling and remodeling of vertebrae to be more mineralized and thus enhance transmission of the axial muscle torque into the thrust force for the C-start predator escape behavior. The prey-predator interaction is expected to occur at closer range between prey fish and predator fish in darker water ...


Hour-Level Resolution On Consumption Pattern Of Substance Abuse, Jarrett Mauk, Rhiannon Huffines, Brittney Nelson, Tara Croft, Bikram Subedi 2019 Murray State University

Hour-Level Resolution On Consumption Pattern Of Substance Abuse, Jarrett Mauk, Rhiannon Huffines, Brittney Nelson, Tara Croft, Bikram Subedi

Scholars Week

Conventional survey-based approaches of determining the consumption statistics of drugs in communities are suffered from non-response biases, and typically underestimate the actual consumption. Time and cost-intensive conventional approaches, therefore, can’t be utilized to determine high-resolution temporal variability in drug consumption. In this study, the temporal trend of consumption of 10 illicit and 26 prescribed neuropsychiatric drugs was determined at hour-level resolution utilizing wastewater-based epidemiology. The hourly composite raw wastewater (every 10 minutes) samples were collected for three consecutive days in a typical week (total of 72 samples), analyzed for target drug residues using UPLC-MS/MS, and back-calculated the consumption ...


Uncertainties Treatment For Wastewater-Based Epidemiological Estimation Of The Consumption Of Illicit And Prescribed Neuropsychiatric Drugs In Two Urban Communities In Kentucky Using Ammonium Normalized Population And Monte Carlo Simulation, Rhinannon Huffines, Tara Croft, Manoj Pathak, Bikram Subedi 2019 Murray State University

Uncertainties Treatment For Wastewater-Based Epidemiological Estimation Of The Consumption Of Illicit And Prescribed Neuropsychiatric Drugs In Two Urban Communities In Kentucky Using Ammonium Normalized Population And Monte Carlo Simulation, Rhinannon Huffines, Tara Croft, Manoj Pathak, Bikram Subedi

Scholars Week

The conventional estimation of the prevalence of substance use in a community based on self-reported surveys typically underestimates the actual consumption. Drug’s residues in raw wastewater collected from the centralized wastewater treatment plants were utilized – Wastewater-Based Epidemiology (WBE) – to determine the consumption rate of illicit and prescribed neuropsychiatric residues in two urban communities in eastern Kentucky and two rural communities in western Kentucky. The ammonical nitrogen content in raw wastewater samples was used to minimize the uncertainty associated with the population dynamicity. Uncertainties associated with the several WBE parameters to back-calculate the consumption rate of drugs such as flow ...


Monitoring Transverse Relaxation Times Of Kerosene-Adulterated Diesel Using Low-Field Nuclear Magnetic Resonance Spectroscopy, Tristen Rumbaugh 2019 Harrisburg University of Science and Technology

Monitoring Transverse Relaxation Times Of Kerosene-Adulterated Diesel Using Low-Field Nuclear Magnetic Resonance Spectroscopy, Tristen Rumbaugh

Experiential Learning Projects

Time-domain nuclear magnetic resonance spectroscopy (TD-NMR) and low-field nuclear magnetic resonance spectroscopy (LF-NMR) are different techniques that vary in the range of magnetic field strengths that they use, which is a determining factor for the type of analysis that can be done. In this study, LF-NMR was used to perform a time-domain analysis of petroleum products, diesel and kerosene. This is a type of analysis which is typically performed using TD-NMR. Diesel and kerosene are two petroleum products that have different characteristics such as viscosity, boiling point, and hydrocarbon length. Diluting, or adulterating, diesel fuels with kerosene is a common ...


Corrosion Studies On Lightweight Automotive Alloys: The Effect Of Microstructure And Fundamental Mechanisms, Wilfred J. Binns 2019 The University of Western Ontario

Corrosion Studies On Lightweight Automotive Alloys: The Effect Of Microstructure And Fundamental Mechanisms, Wilfred J. Binns

Electronic Thesis and Dissertation Repository

Owing to their excellent strength-to-weight ratio and low density, magnesium alloys have the potential to significantly reduce the weight of automobiles leading to decreased emissions and greater range for electrical vehicles. However, the practicality of magnesium alloys for automotive and aerospace applications is severely hindered by their poor corrosion resistance in aqueous environments. Despite intensive research effort, the underlying mechanism(s) responsible for this poor corrosion resistance remains elusive. Further complicating the situation is the presence of secondary microstructures which are necessary for desirable physical properties but lead to microgalvanic coupling which exacerbates the poor corrosion resistance of magnesium alloys ...


The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman 2019 University of Kentucky

The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The sunlight photochemistry of the organic chromophore pyruvic acid (PA) in water generates ketyl and acetyl radicals that contribute to the production and processing of atmospheric aerosols. The photochemical mechanism is highly sensitive to dissolved oxygen content, [O2(aq)], among other environmental conditions. Thus, herein we investigate the photolysis (λ ≥ 305 nm) of 10–200 mM PA at pH 1.0 in water covering the relevant range 0 ≤ [O2(aq)] ≤ 1.3 mM. The rapid consumption of dissolved oxygen by the intermediate photolytic radicals is monitored in real time with a dissolved oxygen electrode. In addition, the rate ...


Infrared Laser Ablation For Biomolecule Sampling, Kelin Wang 2019 Louisiana State University and Agricultural and Mechanical College

Infrared Laser Ablation For Biomolecule Sampling, Kelin Wang

LSU Doctoral Dissertations

In this research, an infrared laser at a wavelength of 3 µm was used to ablate material from tissue sections for biomolecule analysis. Pulsed infrared (IR) irradiation of tissue with a focused laser beam efficiently removed biomolecules, such as proteins, enzymes, DNA, and RNA from tissue sections for further analysis. In a proteomics project, matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) was used to determine regions of interest (ROI) for laser ablation. The matrix was then washed off. By overlaying the MSI generated heat-map, the section was sampled using IR laser ablation and custom stage-control software. Two ROI were ...


Development Of An Innovative And Sustainable One-Step Method For Rapid Plant Dna Isolation For Targeted Pcr Using Magnetic Ionic Liquids, Arianna Marengo, Cecilia Cagliero, Barbara Sgorbini, Jared L. Anderson, Miranda N. Emaus, Carlo Bicchi, Cinzia M. Bertea, Patrizia Rubiolo 2019 Università di Torino

Development Of An Innovative And Sustainable One-Step Method For Rapid Plant Dna Isolation For Targeted Pcr Using Magnetic Ionic Liquids, Arianna Marengo, Cecilia Cagliero, Barbara Sgorbini, Jared L. Anderson, Miranda N. Emaus, Carlo Bicchi, Cinzia M. Bertea, Patrizia Rubiolo

Chemistry Publications

Background

Nowadays, there is an increasing demand for fast and reliable plant biomolecular analyses. Conventional methods for the isolation of nucleic acids are time-consuming and require multiple and often non-automatable steps to remove cellular interferences, with consequence that sample preparation is the major bottleneck in the bioanalytical workflow. New opportunities have been created by the use of magnetic ionic liquids (MILs) thanks to their affinity for nucleic acids.

Results

In the present study, a MIL-based magnet-assisted dispersive liquid–liquid microextraction (maDLLME) method was optimized for the extraction of genomic DNA from Arabidopsis thaliana (L.) Heynh leaves. MILs containing different metal ...


Scale Up Isolation Of Aaptamine For In Vivo Evaluation Indicates Its Neurobiological Activity Is Linked To The Delta Opioid Receptor, Nicole L. McIntosh, Eptisam Lambo, Laura Millan-Lobo, Fei Li, Li He, Phillip Crews, Jennifer L. Whistler, Tyler Johnson 2019 Dominican University of California

Scale Up Isolation Of Aaptamine For In Vivo Evaluation Indicates Its Neurobiological Activity Is Linked To The Delta Opioid Receptor, Nicole L. Mcintosh, Eptisam Lambo, Laura Millan-Lobo, Fei Li, Li He, Phillip Crews, Jennifer L. Whistler, Tyler Johnson

Tyler Johnson

Opioid receptors belong to the large superfamily of seven transmembrane-spanning (7TM) G protein-coupled receptors (GPCRs). As a class, GPCRs are of fundamental physiological importance mediating the actions of the majority of known neurotransmitters and hormones. The Mu, Delta, and Kappa (MOP, DOP, KOP) opioid receptors are particularly intriguing members of this receptor family as they are the targets involved in many neurobiological diseases such as addiction, pain, stress, anxiety, and depression. Recently we discovered that the aaptamine class of marine sponge derived natural products exhibit selective agonist activity in vitro for the DOP versus MOP receptor. Our findings may explain ...


Lake Sediment Analysis At Heron Haven Nature Center, Erik Lato 2019 University of Nebraska at Omaha

Lake Sediment Analysis At Heron Haven Nature Center, Erik Lato

Student Research and Creative Activity Fair

Understanding the chemical composition of a wetland sanctuary lakebed can help us understand how recent developments may have changed the chemical composition. Due to recent dredging by the U.S. Army Corps of Engineers and previous research on water composition at Heron Haven, the goal of this project was to determine the chemical composition as a function of sediment depth. The concentration of seven different metals and nutrients were analyzed in terms of depth. The aluminum, iron, and phosphate concentrations had no real discernible concentration change as a function of depth. There is some hint of a steady increase of ...


Bisthioether Stapled Peptides Targeting Polycomb Repressive Complex 2 Gene Repression, Gan Zhang 2019 The Graduate Center, City University of New York

Bisthioether Stapled Peptides Targeting Polycomb Repressive Complex 2 Gene Repression, Gan Zhang

All Dissertations, Theses, and Capstone Projects

Interactions between proteins play a key role in nearly all cellular process, and therefore, disruption of such interactions may lead to many different types of cellular dysfunctions. Hence, pathologic protein-protein interactions (PPIs) constitute highly attractive drug targets and hold great potential for developing novel therapeutic agents for the treatment of incurable human diseases. Unfortunately, the identification of PPI inhibitors is an extremely challenging task, since traditionally used small molecule ligands are mostly unable to cover and anchor on the extensive flat surfaces that define those binary protein complexes. In contrast, large biomolecules such as proteins or peptides are ideal fits ...


Modeling Solid-Phase Microextraction Of Volatile Organic Compounds By Porous Coatings Using Finite Element Analysis, Bulat Kenessov, Miras Derbissalin, Jacek A. Koziel, Dmitry S. Kosyakov 2019 Al-Farabi Kazakh National University

Modeling Solid-Phase Microextraction Of Volatile Organic Compounds By Porous Coatings Using Finite Element Analysis, Bulat Kenessov, Miras Derbissalin, Jacek A. Koziel, Dmitry S. Kosyakov

Agricultural and Biosystems Engineering Publications

Experimental optimization of analytical methods based on solid-phase microextraction (SPME) is a complex and labor-intensive process associated with uncertainties. Using theoretical basics of SPME and finite element analysis software for the optimization proved to be an efficient alternative. In this study, an improved finite element analysis-based model for SPME of volatile organic compounds (VOCs) by porous coatings was developed mainly focussing on the mass transport in coatings. Benzene and the Carboxen/polydimethylsiloxane (Car/PDMS) coating were used as the model VOC and a porous SPME coating, respectively. It has been established that in the coating, volumetric fractions of Carboxen, PDMS ...


Protein Conformations In The Gas Phase Probed By Mass Spectrometry And Molecular Dynamics Simulations, Maryam Bakhtiari 2019 The University of Western Ontario

Protein Conformations In The Gas Phase Probed By Mass Spectrometry And Molecular Dynamics Simulations, Maryam Bakhtiari

Electronic Thesis and Dissertation Repository

Mass Spectrometry (MS) has been revolutionized by the ability to produce intact gaseous protein ions by electrospray ionization (ESI). The question to what extent these ions retain solution-like conformations under “native” ESI conditions remains a matter of debate. Traditional high-resolution structure determination techniques only report on proteins in the condensed phase. For this reason, MD simulations play an important role in exploring the behavior of gas phase proteins. In this research, mobile and non-mobile proton MD simulations along with mass spectrometry data at 300 K in both positive and negative ion mode indicated that native-like conformations were largely retained. Surface ...


Effect Of Dissolved Salts On The Physiochemical Properties Of Deep Eutectic Solvents, Eleanor Haeska, Megan Radtke 2019 South Dakota State University

Effect Of Dissolved Salts On The Physiochemical Properties Of Deep Eutectic Solvents, Eleanor Haeska, Megan Radtke

The Journal of Undergraduate Research

Green chemistry seeks to make chemical procedures safer, improve reaction efficiency, and utilize environmentally safe reagents. Deep eutectic solvents (DES) have recently become of great interest due to their eco-friendly nature and functionality as solvent for various chemical processes. One key characteristic of DES is their conductive nature and depressed melting point. This project sought to determine the effect of the addition of aqueous solutions of halides on the conductivity of two selected types of DES. Also assessed were the polarity and viscosity of the DES. It can be concluded that aqueous halides had no measureable effect on the conductivity ...


Increased Perchlorate In The Environment Following The 1600 C.E. Huaynaputina Volcanic Eruption, Joseph Gibson, Amanda Shea 2019 South Dakota State University

Increased Perchlorate In The Environment Following The 1600 C.E. Huaynaputina Volcanic Eruption, Joseph Gibson, Amanda Shea

The Journal of Undergraduate Research

Perchlorate is an environmental contaminant that can have adverse health effects on humans. Although our knowledge about how natural perchlorate is formed is very limited, volcanic eruptions are believed to play an important role. An ice core obtained from Summit Station, Greenland was used to study the effects of the Huaynaputina eruption on the amount of perchlorate in the environment. The section of ice core sampled was determined to span the years 1594 through 1610. The results indicate that the Huaynaputina eruption caused a temporary but significant increase in the amount of perchlorate in the atmosphere.


Atomic Force Microscopy Tip-Enhanced Laser Ablation, Fan Cao 2019 Louisiana State University and Agricultural and Mechanical College

Atomic Force Microscopy Tip-Enhanced Laser Ablation, Fan Cao

LSU Doctoral Dissertations

In the present work, an apertureless atomic force microscope (AFM) tip-enhanced laser ablation (TELA) system was developed and investigated. An AFM was coupled to an optical parametric oscillator (OPO) wavelength tunable laser for sample ablation with a submicron sampling size. The AFM was used to image the surface and hold the AFM tip 10 nm above the sample surface. The AFM tip is coated with a layer of gold with a thickness of 35 nm. The incident laser wavelength was tuned in the visible and near-infrared (IR) region and focused on the AFM tip. With the tip-enhancement effect, ablation craters ...


Precipitation And Coacervation In Polyelectrolyte-Colloid Systems, Fatih Comert 2019 University of Massachusetts Amherst

Precipitation And Coacervation In Polyelectrolyte-Colloid Systems, Fatih Comert

Doctoral Dissertations

Complex coacervation between oppositely charged polyelectrolytes (PEs) and colloids (i.e. micelles and proteins) has increasingly become popular due to the use of these materials in a range of applications including but not limited to personal care, biomaterials, protein purification, and food science. In taking advantage of complex coacervation, which is a liquid-liquid phase separation, precipitation has always represented a problem by introducing inhomogeneities, irreversibility and irreproducible kinetics. Therefore, understanding the dominant factors driving the formation of precipitates is important to control outcomes.

In this work, we have performed comparative studies of coacervation and precipitation in model PE-colloid systems to ...


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