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Full-Text Articles in Physical Sciences and Mathematics

Capturing Latent Abilities And Latent Capacities Of Professional Golfers Using Nonlinear Mixed Effects Growth Modeling, Mac Wetherbee Jun 2024

Capturing Latent Abilities And Latent Capacities Of Professional Golfers Using Nonlinear Mixed Effects Growth Modeling, Mac Wetherbee

Electronic Theses and Dissertations

This study demonstrates an effective and innovative approach to measuring the latent athletic abilities and capacities of professional golfers. I used nonlinear mixed effects growth modeling (e.g., Dynamic Measurement Modeling) to measure professional golfers’ ability levels and capacities for improvement. I accomplished this using a two-stage modeling approach. First, a crossed linear mixed effects model estimated each player’s ability level in each year. In the second stage, I used the results from the first stage to estimate several candidate nonlinear growth trajectories for players’ abilities over time. The quadratic growth trajectory was the best-fitting of these trajectories and was used …


Bridging The Geometric And Quantum Information Of Structured Light, Andrew Alexander Voitiv Jun 2024

Bridging The Geometric And Quantum Information Of Structured Light, Andrew Alexander Voitiv

Electronic Theses and Dissertations

In this Dissertation, we review the several advances we have developed for preparing and measuring the geometric and quantum information of structured light. The geometric phase acts as a memory of transformations undertaken by physical processes; quantum entanglement underpins quantum information science which explores the theoretical and technological applications of nonclassical correlations. Beginning with classical light, we demonstrate novel experiments and measurements of geometric phase that are enabled by spatially structuring laser beams. We then extend those concepts to complement the richer possibilities within quantum optics. Our work covers new abilities in tailoring and measuring the phase content of spatially-structured …


Establishment Of A Research Site At The Kennedy Mountain Campus For The Observation Of Airborne Particulate Matter, Alyssa Knaus Jun 2024

Establishment Of A Research Site At The Kennedy Mountain Campus For The Observation Of Airborne Particulate Matter, Alyssa Knaus

Undergraduate Theses, Capstones, and Recitals

This thesis explored particulate matter (PM) concentrations at two sites within the Colorado Front Range. The study utilized two models of PurpleAir PM sensors, Flex and SD-II, to provide real-time, accessible data on PM1, PM2.5, and PM10 mass concentrations with the goal of establishing the first research site at the Kennedy Mountain Campus (KMC). The first of the two sites used during this study was at a suburban location outside of Denver, CO. This period was used as an instrument intercomparison period in order to conduct instrument analysis. The initial findings from this period found significant correlations between PM concentration …


Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke Jun 2024

Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke

Undergraduate Theses, Capstones, and Recitals

Science surrounding the use of low-cost sensors (LCS) to monitor air quality is rapidly expanding to satisfy the need to fill in regional air quality data gaps. This project evaluated the suitability of two types of LCS: Modulair-PM and PurpleAir (SD and Flex models) as efficient means to measure airborne particulate matter. The study involved physical installation of nine co-located sensors at a suburban site in Denver, connectivity troubleshooting as necessary, and data analysis/modeling of data over multiple months (19 weeks). PM data was compared between individual sensors of the same type, as well as across the two different sensor …


Spin And Charge Transport In Metallic Ferrimagnets And Disordered Magnetic Oxides, Leopoldo A. Hernandez Jun 2024

Spin And Charge Transport In Metallic Ferrimagnets And Disordered Magnetic Oxides, Leopoldo A. Hernandez

Electronic Theses and Dissertations

Recent efforts have been exploring the use of thin film synthetic ferrimagnets and disordered magnetic oxides for applications in spintronic devices. Due to the antiferromagnetic exchange interaction, ferrimagnetic materials offer the ultrafast dynamics of the antiferromagnetic exchange, with a net magnetization that can be influenced externally. With two, or more, competing ferromagnet sublattices, interesting properties arise that depend on the final magnetic landscape after growth of the material and it’s inherent magnetic anisotropy energies. Properties such as magnetic compensation temperatures, and perpendicular magnetic anisotropy are attractive for applications in spintronic memory and logic devices, some already being implemented in MRAM …


Comparing The Preparation Of Youth Services Librarians To Their On-The-Ground Experiences: A Grounded Theory Study Incorporating Criticism And Connoisseurship, Anne Holland Jun 2024

Comparing The Preparation Of Youth Services Librarians To Their On-The-Ground Experiences: A Grounded Theory Study Incorporating Criticism And Connoisseurship, Anne Holland

Electronic Theses and Dissertations

The purpose of this study was to better understand the on-the-ground preparation of youth services librarians, in contrast to their professional training in Master’s of Library Science (MLIS) programs. Classic Grounded Theory was the predominant methodology for this qualitative study, and elements of Criticism and Connoisseurship were also utilized. Document review, interviews, and journaling activities with ten participants were the primary methods of data collection. Key findings from this dissertation include a grounded theory explaining the current state of preparation for youth services librarianship, and multiple avenues for further study.


Extending The Utility Of Ant Colony Optimization Through The Incorporation Of An Intraclass Correlation Coefficient To Assess For Rater Consistency, Mark Leveling Jun 2024

Extending The Utility Of Ant Colony Optimization Through The Incorporation Of An Intraclass Correlation Coefficient To Assess For Rater Consistency, Mark Leveling

Electronic Theses and Dissertations

Ant Colony Optimization (ACO) is a flexible algorithm designed to solve complex combinatorial problems. While the method was derived from the behavior of ants by researchers in the field of computer science, its application to solving complex combinatorial problems is widespread in a growing number of fields in behavioral science, including psychometrics. Over the last two decades, psychometricians have adapted ACO to measurement model specification problems with the intention of generating measurement models that express measurement model fit and reliability within the standards of what is considered acceptable. Additionally, psychometricians have used ACO to generate shortened versions of existing measures …


A Geospatial And Machine Learning Framework For Forecasting Ground Level Ozone Pollution, William J. Keenan Jun 2024

A Geospatial And Machine Learning Framework For Forecasting Ground Level Ozone Pollution, William J. Keenan

Electronic Theses and Dissertations

The major detrimental health effects of ground-level ozone (GLO) pollution make it imperative that both policy makers and ordinary citizens have access to high accuracy, high-resolution forecasts of their local area. Recently, advancements in computing power have made it possible to apply artificial intelligence (AI) techniques to a variety of big data modelling problems, including GLO forecasting and estimation. Of these AI methods, deep neural networks (DNN) have demonstrated the highest accuracy due to their ability extract non-linear relationships from high dimensional, noisy data inputs.

This research effort uses novel data sources, namely NOAA’s High Resolution Rapid Refresh (HRRR) meteorology …


Evaluating The Effect Of Domain-Specific Large Language Models On Question And Response, Phillip D. Crippen Jun 2024

Evaluating The Effect Of Domain-Specific Large Language Models On Question And Response, Phillip D. Crippen

Electronic Theses and Dissertations

Large Language Models have emerged to great fanfare in the Information Technology market. Business and Information Technology leaders are currently exploring ways to apply these models to assist their organizations in executing business processes and generating innovation. Software vendors, consultants, and academics promote various approaches to making Large Language Models work effectively for business. However, little academic literature is available today that quantifies the degree of improvement possible with these domain-specific approaches over the standard capabilities of generalized Large Language Models.

The study seeks to quantify the benefits of one approach, Retrieval Augmented Generation. The study uses a collection of …


How Well Do Nature-Based Solutions To Climate Change Address Gender Equity?, Stephanie Efua Yamoah Jun 2024

How Well Do Nature-Based Solutions To Climate Change Address Gender Equity?, Stephanie Efua Yamoah

Electronic Theses and Dissertations

As the climate crisis continues to deepen, there have been calls for adaptation and mitigation approaches that rely on nature-based solutions. These solutions are approaches that offer the potential to reduce and remove greenhouse gas emissions. Examples include forest restoration, coastal wetland conservation, and no-till agriculture, among other practices. In this thesis, I employ an intersectional feminist political ecology perspective to critically examine the integration of gender equity within such nature-based solutions. I make two interrelated arguments using a qualitative methodology and an intensive case study of three projects in Ghana. First, I argue that women’s participation in nature-based solutions …


Using Historic Glacial Data And Gis To Predict Mount Rainier National Park’S Glacial Future, Daniel Kincaid Jun 2024

Using Historic Glacial Data And Gis To Predict Mount Rainier National Park’S Glacial Future, Daniel Kincaid

Geography and the Environment: Graduate Student Capstones

Will Washington state have glaciers 100 years from now (year 2124)? Due to generally warmer weather glaciers are largely in retreat globally, including the glaciers in Washington state. In Washington state summer glacial meltwater plays a vital role in the survival of wildlife and is needed for human purposes that include recreation, power generation, drinking, agricultural, and industrial. This project looked at the most resilient glaciers in Washington state, the glaciers at Mount Rainier National Park. Historic measurements were used in an exponential growth calculation to project the amount in acres each glacier at Mount Rainer will advance or retreat …


Near-Surface Thermodynamic Influences On Evaporation Duct Shape, Sarah E. Wessinger, Daniel P. Greenway, Tracy Haack, Erin E. Hackett Jun 2024

Near-Surface Thermodynamic Influences On Evaporation Duct Shape, Sarah E. Wessinger, Daniel P. Greenway, Tracy Haack, Erin E. Hackett

Marine Science

This study utilizes in situ measurements and numerical weather prediction forecasts curated during the Coupled Air–Sea Processes Electromagnetic Ducting Research (CASPER) east field campaign to assess how thermodynamic properties in the marine atmospheric surface layer influence evaporation duct shape independent of duct height. More specifically, we investigate evaporation duct shape through a duct shape parameter, a parameter known to affect the propagation of X-band radar signals and is directly related to the curvature of the duct. Relationships between this duct shape parameter and air sea temperature difference (ASTD) reveal that during unstable periods (ASTD < 0), the duct shape parameter is generally larger than in near-neutral or stable atmospheric conditions, indicating tighter curvature of the M-profile. Furthermore, for any specific duct height, a strong linear relationship between the near-surface-specific humidity gradient and the duct shape parameter is found, suggesting that it is primarily driven by near-surface humidity gradients. The results demonstrate that an a priori estimate of duct shape, for a given duct height, is possible if the near-surface humidity gradient is known.

This article was published Open Access …


Visualization Of Indiana And Northern Long-Eared Bats Using Spline Surfaces To Enable Targeted Land Management, Devin Escue Jun 2024

Visualization Of Indiana And Northern Long-Eared Bats Using Spline Surfaces To Enable Targeted Land Management, Devin Escue

Geography and the Environment: Graduate Student Capstones

This project introduces a Bat Visualization Tool to help manage habitats for threatened bat species while considering broader ecosystem dynamics. It integrates data from acoustic bat surveys at the Corriell Nature Preserve in Iowa. The tool attaches spatial context to non-spatial survey data, weights species calls based on statistical p-values, and creates visual bat species distribution maps using spline surfaces. It also generates future survey locations based on these patterns. By using geospatial analysis and statistics, the tool identifies priority areas for conservation actions, focusing on factors like forest composition, roosting preferences, and land cover types that affect bat habitat …


Gis-Based Dashboard For Data Analysis And Visualization At The Water Hub In Franschhoek, South Africa, Liliana Rosa Simon Jun 2024

Gis-Based Dashboard For Data Analysis And Visualization At The Water Hub In Franschhoek, South Africa, Liliana Rosa Simon

Geography and the Environment: Graduate Student Capstones

This capstone project analyzes the land use change in the Franschhoek Valley, South Africa, and implements this information into an ArcGIS Experience Builder Dashboard. The development of an ArcGIS Experience Builder is utilized as a tool for improved spatial data communication at The Water Hub. An increase in urban development in the informal settlement upstream of the Stiebeuel River in the catchment basin north of the Water Hub research institute is found. The capstone uses geographic information systems, remote sensing, and ArcGIS Experience Builder to integrate spatial data into the Water Hub’s standard operating procedures. It highlights the importance of …


Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin Jun 2024

Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin

University Honors Theses

The following paper will be exploring a pilot methodology of a drain gauge system I built that’s used to calculate stormwater runoff from ecoroofs in Portland, Oregon. The drain gauge is a less studied technique for measuring ecoroof runoff, but holds high potential for developing better monitoring and management of ecoroofs within the city of Portland. What separates this stormwater runoff capturing device apart from other stormwater runoff calculation techniques is its adaptable design and simple installation. The drain weir can be placed in any roof drain that an ecoroof has been installed simply by placing it into a roof …


Technology And Homelessness: How Website Design And Blockchain Technology Could Impact The Unhoused, Casey Pratt Jun 2024

Technology And Homelessness: How Website Design And Blockchain Technology Could Impact The Unhoused, Casey Pratt

Undergraduate Theses, Capstones, and Recitals

Although technology could be used to combat inequality, it is instead increasing it. This paper discusses how the unhoused population suffers at the hand of technological inequality despite being relatively offline. It presents theories on how this would change if we reapproached how technology is used to assist the unhoused. It suggests implementing blockchain as a resource as well as modifying the websites built to assist in accessing benefits. Employees at shelters are interviewed for this paper about their experiences with using digital resources to rehouse and restabilize the vulnerable. They are asked how the sites can be improved for …


Statistical Modeling Of Knee Morphology And Material Properties Considering Diverse Populations, Gabrielle Jeannine Kindy Jun 2024

Statistical Modeling Of Knee Morphology And Material Properties Considering Diverse Populations, Gabrielle Jeannine Kindy

Electronic Theses and Dissertations

Total Knee Arthroplasty (TKA) is a widely performed surgical procedure aimed at alleviating pain and restoring function in patients with severe knee osteoarthritis. Despite its general success, disparities in postoperative outcomes have been observed across different racial and ethnic groups, with minority populations often experiencing less favorable results. One potential avenue for improving the generalizability of orthopaedic implants is using Statistical Shape and Intensity Models (SSIMs), which can be used to incorporate patient variability directly into the orthopaedic medical device development workflow through population-based finite element analysis.

This work aimed to construct an SSIM from a diverse subject set, incorporating …


A Cost-Effective Enzyme Kinetics And Inhibition Model For Biochemistry Education And Research, Lauren Vandee, Alyssa Teague, Taylor East, Kim Rhona Jacinto, Macie Carter, Jacey Totty, Paul D. Adams, Djamali Muhoza Jun 2024

A Cost-Effective Enzyme Kinetics And Inhibition Model For Biochemistry Education And Research, Lauren Vandee, Alyssa Teague, Taylor East, Kim Rhona Jacinto, Macie Carter, Jacey Totty, Paul D. Adams, Djamali Muhoza

Chemistry & Biochemistry Faculty Publications and Presentations

Enzyme kinetics and inhibition studies are crucial in biochemistry education and research. Conventional methods often require expensive equipment and reagents, potentially limiting their accessibility in limited resource settings. Our approach sought to develop a cost-effective experimental design for studying enzyme kinetics and inhibition. Lactase was chosen as a protein model and its activity was investigated by measuring glucose production from lactose hydrolysis. In the study, commercially available lactase pills were used as an enzyme source, while milk was used as a substrate. Instead of scientific equipment, glucometers were used to measure lactase activity. Enzyme kinetics were evaluated using Michaelis–Menten and …


Differential Elliptic Flow Analysis Of Hadrons With Different Wuark Content In Simulated Pp Collisions, Elhussein Osama Jun 2024

Differential Elliptic Flow Analysis Of Hadrons With Different Wuark Content In Simulated Pp Collisions, Elhussein Osama

Theses and Dissertations

According to current physics theories, it is assumed that in the first microsecond after the big bang, the universe was in a state of matter called Quark-Gluon Plasma (QGP), where the fundamental consistent of matters (quarks and leptons), were highly energetic, and floating around freely. Searching for such phase of matter; as the possible earliest signatures after the big bang, and among many other interesting experimental measurements, the jet quenching and elliptic flow are the most important ones, in the heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) experiments.

The azimuthal anisotropy …


Activity Descriptors As Tools For Designing Highly Efficient Electrocatalysts For Water Splitting, Aya Gomaa Jun 2024

Activity Descriptors As Tools For Designing Highly Efficient Electrocatalysts For Water Splitting, Aya Gomaa

Theses and Dissertations

There is an uprising urge to design efficient, active, and durable catalysts to achieve sustainable hydrogen production. The unambiguity of which material should be used pushed the scientific community to devote enormous efforts in exploring different elements with different ratios on trial and error bases. However, the bridge between the theoretical calculation and the experiments introduced a new realm of designing efficient catalysts by introducing the concept of activity descriptors. In the first part of the thesis, the ability to convert waste stainless steel (SS) 316L meshes into highly efficient and durable oxygen evolution reaction (OER) catalysts is demonstrated. The …


The Use Of Laja In Construction In Ancient Mesoamerica: A View From The Southern Gulf Lowlands Of Veracruz, Mexico, Lauren E. Smith Jun 2024

The Use Of Laja In Construction In Ancient Mesoamerica: A View From The Southern Gulf Lowlands Of Veracruz, Mexico, Lauren E. Smith

Steeplechase: An ORCA Student Journal

The archaeology of the southern Gulf lowlands of Veracruz, Mexico is notable for its research pertaining to the Olmec culture (Jaime-Riveron 2016; Loughlin 2012; Pool 2006). The region was home to the Colossal Olmec Heads: large, easily identifiable sculptures crafted from the volcanic rock of the Tuxtlas Volcanic Field. The use of volcanic resources in such grand presentations may instill a bias in the research of some archaeologists, but it is important to consider how these and other volcanic resources might have been used in everyday life (e.g., Jaime-Riveron 2016: 86). The consolidated volcanic ash in this region is referred …


Information Technology In The Christian Sphere, Kaylen Frazee Jun 2024

Information Technology In The Christian Sphere, Kaylen Frazee

NEXUS: The Liberty Journal of Interdisciplinary Studies

No abstract provided.


Circling The Square: Computing Radical Two, Isaiah Mellace, Joshua Kroeker Jun 2024

Circling The Square: Computing Radical Two, Isaiah Mellace, Joshua Kroeker

NEXUS: The Liberty Journal of Interdisciplinary Studies

Discoveries of equations for irrational numbers are not new. From Newton’s Method to Taylor Series,there are many ways to calculate the square root of two to arbitrary precision. The following method is similar in this way, but it is also a fascinating derivation from geometry that has applications to other irrationals. Additionally, the equation derived has some properties that may lead to fast computation. The first part of this paper is dedicated to deriving the equation, and the second is focused on computer science implementations and optimizations.


Crystallographic Analysis Of The Dorsal Spine Of Squalus Suckleyi, John V. Karavitis Jun 2024

Crystallographic Analysis Of The Dorsal Spine Of Squalus Suckleyi, John V. Karavitis

College of Science and Health Theses and Dissertations

The dorsal spine of the spiny dogfish, Squalus acanthias, has been used for age determination of individual specimens since the 1930s. Scientific literature regarding the dorsal spine has to date always referred to it as having an enamel exterior, with a dentin interior surrounding a central pulp cavity. This is similar to the structure observed in a human tooth.

The dorsal spine is composed of cartilage-based tissue that contains bioapatite. Bioapatite is a mixture of hydroxyapatite, Ca10(PO4)6(OH)2 (a calcium salt of phosphoric acid), and other biological material, e.g. calcium carbonate, CaCO3 …


Effect Of Quince Seed Gum (Qsg) On The Performance Of Injectable Hyaluronic Acid Hydrogels In Terms Of The Rheological, Morphological, And Mechanical Aspect, Serdar Kolay, Ni̇lhan Kayaman Apohan, Erdi̇nç Babuç, Gökay Gün Jun 2024

Effect Of Quince Seed Gum (Qsg) On The Performance Of Injectable Hyaluronic Acid Hydrogels In Terms Of The Rheological, Morphological, And Mechanical Aspect, Serdar Kolay, Ni̇lhan Kayaman Apohan, Erdi̇nç Babuç, Gökay Gün

Turkish Journal of Chemistry

Injectable hydrogels play an important role in tissue engineering as a filling and repairing material. This study aimed to develop a new injectable hydrogel based on hyaluronic acid (HA) and quince seed gum (QSG) and investigate the effect of QSG on hydrogel performance. The amount of unreacted 1,4-Butanediol diglycidyl ether (BDDE) is maintained at an undetectable level for HA-QSG hydrogels. Amino acid analysis showed that the HA-QSG hydrogel had rich amino acid concentrations of leucine, arginine, and valine. After thermal sterilization, the elastic modulus of HA-QSG gels for dermal and intra-articular filler applications is 63 Pa and 92 Pa respectively. …


Antiviral And Cytotoxic Activities And Chemical Profiles Of Two Species Of Abies Nordmanniana From Türkiye, Nazli Sarikahya, Gaye Sümer Okkali, Furkan Ozan Çöven, Sevda Zeinali̇, Gülce Gucur, Ayşe Di̇la Çağlar, Ece Uyar, Ahmet Ceyhan Gören, Ayşe Nalbantsoy Jun 2024

Antiviral And Cytotoxic Activities And Chemical Profiles Of Two Species Of Abies Nordmanniana From Türkiye, Nazli Sarikahya, Gaye Sümer Okkali, Furkan Ozan Çöven, Sevda Zeinali̇, Gülce Gucur, Ayşe Di̇la Çağlar, Ece Uyar, Ahmet Ceyhan Gören, Ayşe Nalbantsoy

Turkish Journal of Chemistry

Abies is an important genus of the family Pinaceae, with about 50 species found in the highlands of Asia, Europe, North Africa, and North and Central America. The principal aim of the present work was to investigate the chemical content and biological potential of the resin and cone from Abies nordmanniana subsp. bornmulleriana and Abies nordmanniana subsp. equi-trojani, respectively. The flavonoid and phenolic contents of the resin and cones were evaluated using liquid chromatography-high resolution mass spectrometry (LC-HRMS). Additionally, the essential oil and fatty acid compositions were analyzed using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID).. Cytotoxicity …


Theoretical Study On The Insertion Reaction Of The Stannylenoid H2snlif With X-H Bonds (X = N, O, F), Shuo Wu, Bingfei Yan, Shaoli Liu, Wenzuo Li Jun 2024

Theoretical Study On The Insertion Reaction Of The Stannylenoid H2snlif With X-H Bonds (X = N, O, F), Shuo Wu, Bingfei Yan, Shaoli Liu, Wenzuo Li

Turkish Journal of Chemistry

The insertion reactions of p-complex (RP) and three-membered ring configuration (RS) of stannylenoid H2SnLiF with NH3, H2O and HF have been studied theoretically by quantum chemical calculation. The structures of reactants, precursors, transition states, intermediates and products have been fully optimized at the M06-2X/def2-TZVP level. The single point energy of all fixed points were calculated using the QCISD method. The calculation results show that the three-membered ring configuration is easier to conduct the insertion reaction. Comparing the reaction energy barriers of RP, RS to NH3, H2O and HF, we found that the difficulty of the insertion reaction is NH3 > H2O …


Senggani Fruit (Melastoma Malabathricum Linn.) Extract As A Natural Indicator In Ph-Responsive Pva-Taro Starch Plastic Packaging, Rika Risma Dewi, Intan Syahbanu, Winda Rahmalia Jun 2024

Senggani Fruit (Melastoma Malabathricum Linn.) Extract As A Natural Indicator In Ph-Responsive Pva-Taro Starch Plastic Packaging, Rika Risma Dewi, Intan Syahbanu, Winda Rahmalia

Turkish Journal of Chemistry

Polyvinyl alcohol (PVA)-starch-based bioplastics are widely used in many applications. pH-responsive plastic packaging was produced through the incorporation of senggani (Melastoma malabathricum Linn.) fruit extract into PVA-taro starch-based plastic packaging. The objective of this research was to examine the characteristics of senggani fruit extract under different pH conditions and explore its application as a pH indicator in intelligent packaging. The senggani fruit was extracted through the maceration method using a solvent comprising 96% ethanol and 3% citric acid, with a ratio of 85:15 (v/v). The senggani fruit extract solution underwent color changes, appearing pink at pH levels below 6, pale …


Dft Modeling Of Water-Assisted Hydrogen Peroxide Formation From A C(4a)-(Hydro)Peroxyflavin, Yilmaz Özkiliç Jun 2024

Dft Modeling Of Water-Assisted Hydrogen Peroxide Formation From A C(4a)-(Hydro)Peroxyflavin, Yilmaz Özkiliç

Turkish Journal of Chemistry

The cofactor of a class A monooxygenase is reduced at an external location of the enzyme and is subsequently pulled back into the active site after the reduction. This observation brings the question; is there any defense mechanism of the active site of a monooxygenase against the formation of the harmful hydrogen peroxide from the reactive C(4a)-(hydro)peroxide intermediate? In this study, the barrier energies of one to three water molecule-mediated uncoupling reaction mechanisms in water exposed reaction conditions were determined. These were found to be facile barriers. Secondly, uncoupling was modeled in the active site of kynurenine 3-monooxygenase complex which …


Design And Characterization Of Phosphonic Acid-Functionalized Grafted Sepiolite Nanohybrids And Their Adsorption Studies For Removal Of Copper Ions From Aqueous Solution, Mehwish Tahir, Asif Raza, Amara Nasir, Tariq Yasin, Shamila Imtiaz Jun 2024

Design And Characterization Of Phosphonic Acid-Functionalized Grafted Sepiolite Nanohybrids And Their Adsorption Studies For Removal Of Copper Ions From Aqueous Solution, Mehwish Tahir, Asif Raza, Amara Nasir, Tariq Yasin, Shamila Imtiaz

Turkish Journal of Chemistry

In this study, we synthesized novel, economically efficient phosphonic acid-functionalized grafted sepiolite nanohybrids for selective elimination of copper ions from water. These nanohybrids were prepared by graft polymerization of glycidyl methacrylate onto sepiolite. We utilized free radical graft polymerization to graft glycidyl methacrylate (GMA) onto silanized sepiolite. The nanohybrids obtained exhibited a grafting percentage of 479% at 0.3 g of KPS initiator, 15% GMA monomer, and after 4 h of reaction. In pursuit of selectively removing metal ions from water, the nanohybrid with the highest grafting (PGE3) was chemically treated with phosphoric acid to introduce phosphonic acid groups on it. …