Chemistry Commons^™

Crystal Growth, Thermal, Optical, Magnetic And Electrochemical Properties Of Mo2Ta2O11, Md Abdullah Al Muhit, Alevtina A. Maksimova, Sean C. Wechsler, Habiba Binte Kashem, Gopabandhu Panigrahi, Gregory Morrison, Morgan Stefik, Hans Conrad Zur Loye

Faculty Publications

Single crystals of the transition metal oxide Mo2Ta2O11 were grown for the first time using molten flux synthesis. The compound crystalizes in the trigonal space group R 3‾m (no. 166) with lattice parameters a = b = 5.6267(1) Å and c = 25.1424(6) Å and a unit cell volume of 689.36(3) ų. The structure of Mo2Ta2O11 is composed of alternating layers of TaO6 octahedra and MoO4 tetrahedra connected via corner-sharing. CaH2 was used to achieve a partial low temperature reduction of Mo2Ta2O11. The electrochemical lithiation of polycrystalline Mo2Ta2O11 was also investigated for the first time. Mo2Ta2O11 underwent a …

Structure-Activity Relationships Of Isothiourea And Silicon Phthalocyanine Catalysts, Christian J. Harrison

Theses and Dissertations

Efficient organic synthesis often relies on improving catalyst designs and investigating reaction mechanisms to accomplish feats such as high stereoselectivity, low catalyst loadings, and performing sustainable chemistry. Within the field of organocatalysis, intermolecular interactions between a catalyst and a substrate are a large contributing factor to the control of a reaction, including rate and selectivity. Investigating mechanisms can provide information on the type of intermolecular interactions occurring in the reaction, aiding future reaction and catalyst development. This dissertation will explore two recent projects and how probing intermolecular interactions through simple modifications provides information useful for new catalyst designs and properties. …

Exploring And Characterizing Organic Chemistry Students’ Meaningful Engagement In Science Practices, John Zhou

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Undergraduate organic chemistry frequently engages students in key science practices such as analyzing and interpreting spectroscopic data and constructing explanations through reaction mechanisms. However, these activities are often framed as procedural tasks rather than as tools for constructing knowledge. As a result, students may develop incomplete understanding of these practices, making it harder for them to see how scientific knowledge is generated and to use them meaningfully as tools for sensemaking. To better understand how students take up these practices as epistemic tools, three qualitative studies were conducted in this dissertation to investigate how undergraduate organic chemistry students reason with …

Electrochemistry Behind Pfas: Mechanistic And Analytical Approach For Sensing And Degradation Strategies, Jonathan Josue Calvillo Solis

Open Access Theses & Dissertations

Understanding the fundamental electrochemistry of perfluoroalkyl substances (PFAS) is key to developing effective water remediation and sensing strategies. This work explores the thermodynamics and kinetics of perfluorooctanoic acid (PFOA) electroreduction, focusing on C-F bond cleavage. These insights were applied to design a highly sensitive electrochemical sensor for detecting trace levels of PFOA in water. This dissertation focuses on the electrochemical investigation of the reduction reaction of PFOA in aqueous and organic media employing different electrode materials. This exploration allows to understand the defluorination reaction of PFAS to further propose potential strategies for water treatment and PFOA electrosensing. Through electrochemical, spectroscopical …

Electrocatalytic Degradation Of Methylene Blue Using Graphene Oxide, Antimony Oxide, And Graphene Oxide-Supported Antimony Oxide Ink-Based Electrodes, Maria Irene Myers Armas

Theses and Dissertations

This study investigates the electrocatalytic degradation of methylene blue (MB) using copper mesh electrodes coated with graphene oxide (GO), antimony oxide (Sb₂O₃), and their composite (GO/Sb₂O₃). These materials were evaluated across a pH range of 2 to 8 using sodium sulfate as the supporting electrolyte. UV-Vis spectroscopy at 665 nm confirmed dye degradation, with removal efficiencies reaching up to 95% at pH 2. However, degradation decreased at higher pH, with 40 – 60% removal at pH 8, depending on the electrode. Kinetic analyses revealed optimum performance under acidic conditions. GO/Sb₂O₃ electrodes demonstrated the most consistent and effective performance across all …

Quantifying Biomass Burning Impacts On Soil Nox Emissions And Reactive Nitrogen Cycling, Olivia Rae Steinbeck

Theses and Dissertations

Nitrogen oxides (NOx = NO + NO₂) are trace gases that play a critical role in the atmosphere by influencing air quality, oxidation chemistry, and the deposition of fixed nitrogen. Historically, NOx emissions have been primarily linked to anthropogenic sources such as fossil fuel combustion, industrial activities, and agriculture. However, as successful legislation has significantly reduced these emissions, the relative importance of natural NOx sources has become an increasing concern. Soil NOx emissions are of particular interest due to their strong temperature dependence and their connection to global climate change. Rising global temperatures are expected to accelerate soil NOx emissions …

Quinone-Mediated Extracellular Electron Transfer In Escherichia Coli During Glucose Oxidation Metabolism, Megan Danielle Whisonant

Theses and Dissertations

The growing global demand for energy, ongoing reliance on fossil fuels, and increasing water pollution from industrial and anthropogenic sources present significant environmental challenges. In response to these issues, renewable and sustainable energy sources offer substantial potential for reducing dependence on fossil fuels and ensuring access to clean water. Microbial electrochemical systems (MESs) have emerged as promising, eco-friendly solutions for energy-efficient wastewater treatment and bioremediation. A key challenge in MESs development is facilitating effective electron transfer between microorganisms and electrode surfaces. The first chapter of this thesis discusses the fundamentals of MES types, explains mechanisms of extracellular electron transfer, and …

The Potential Importance Of Microenvironment On Polymer Bound Chemical Reagents, Nathan Joseph Halsteter

Theses and Dissertations

In this thesis will provide a brief history of polymer bound reagents, their uses, and advancements. The importance of polymer microenvironments will be explored using a model kinetic resolution reaction utilizing polymer bound reagents to observe how changes in a polymer’s microenvironment effects the yield and selectivity of a reaction. It was found that there are copious factors that affect polymer bound reagents, and no direct conclusion could be drawn from the study.

Reactivity Of Redox-Active Carboranyl Diphosphines And Carboranyl Diphosphoniums: Metal-Free Pathways For Small Molecule Activations And Transformations, Amanda Lynn Humphries

Theses and Dissertations

Transition metal catalysis has been an integral part of synthetic chemistry for its ability to selectively activate strong substrate bonds, promoting numerous crucial transformations. Despite their utility, the precious metals that are often employed in these catalytic reactions suffer from several drawbacks (including high toxicity, low natural abundance, high costs, and low sustainability), increasing the motivation to design suitable metal-free alternatives. Towards this end, several ambiphilic main-group systems have been devised to show metal-like reactivity, such as carbenes, borylenes, and Frustrated Lewis Pairs. This manuscript will describe the ambiphilic reactivity of carborane-based phosphorus compounds, highlighting the unique metallomimetic reactivity that …

Characterizing Dissolved Organic Matter Composition In A Southeastern United States Watershed, Gwendolyn Marcelette Hopper

Theses and Dissertations

Dissolved organic matter (DOM) has important roles in many biogeochemical cycles. DOM is primarily composed of dissolved organic carbon (DOC), nitrogen, and phosphorus, and the processing of DOM is important for nutrient regulation and carbon cycling. In the coastal plains of the southeastern United States, there are many rivers and streams known as “blackwaters” with exceptionally high concentrations of chromophoric dissolved organic matter (CDOM) leached from terrestrial soils, coinciding with a region experiencing some of the nation’s highest rates of development. As changes in land use and climate continue to occur, DOM composition from natural to anthropogenically impacted systems can …

Determination Of Structure-Function Relationships In Hybrid Catalysts On Metal Oxide Supports, Joseph John Kuchta

Theses and Dissertations

Transition metal catalysis has revolutionized chemical synthesis, enabling efficient and selective transformations critical to the pharmaceutical, agricultural, and materials industries. However, traditional methods often rely on expensive, non-sustainable metals and harsh reaction conditions that generate significant waste. This dissertation explores a series of innovations aimed at bridging the gap between homogeneous and heterogeneous catalysis through the development of hybrid catalysts. These systems combine the molecular precision of homogeneous catalysts with the stability and practicality of heterogeneous supports, offering a pathway to more sustainable and scalable catalytic processes.

The first area of focus investigates nickel-based hybrid catalysts as a cost-effective and …

Rapid Charging Lithium-Ion Batteries: Structure, Morphology, And Methodology, Sean Cade Wechsler

Theses and Dissertations

The initial commercialization and subsequent development of the lithium-ion battery (LIB) in 1991 has revolutionized the way that humans power devices, cars, and homes and led to the advent of many technologies that seemed impossible just half a century ago. As LIBs are integrated into more of daily life through handheld devices, wearable medical devices, transportation, and grid-level energy storage, the demand for fast charging and high energy density increases rapidly. To design a battery with these favorable qualities, an understanding of the effect of electrode crystal structure and electrode morphology on the ionic/electronic transport and failure modes must be …

Exploring The Self-Assembly Of Functional Bis-Urea Macrocycles: M-Terphenyl Bis Urea Macrocycles And Triphenylamine Bis-Urea Macrocycles, Gamage Isuri Pramodya Wijesekera

Theses and Dissertations

Porous materials have gained significant attention due to their diverse applications in catalysis, separation, and molecular storage. Among them, self-assembled macrocycles represent a unique class of functional materials that leverage non-covalent interactions to form well-defined architectures with pores of controlled size. This thesis explores the design, synthesis, and self-assembly of bis-urea macrocycles in both solid-state and solution-phase environments, with a particular focus on supramolecular polymerization mechanisms and the emergence of kinetically trapped states.

The first chapter of this thesis presents a detailed overview of self-assembled porous materials, categorizing them based on pore dimensions and discussing their significance in catalysis, separation, …

In Vivo Analysis Of Fe-S Cluster Assembly And Iron Homeostasis In Escherichia Coli, Dexter Mclaurin Reasons

Theses and Dissertations

Iron-sulfur (Fe-S) clusters are an essential cofactor for a wide range of cellular processes, and their assembly and storage require tight regulation.

In Escherichia coli (E. coli), there are two pathways of Fe-S cluster assembly, the Isc and the Suf pathways. The Isc pathway is used under good growth conditions, and the Suf pathway is used under iron starvation and oxidative stress conditions. Once the cluster has been assembled on the scaffold protein of either pathway, it is transferred to Fe-S cluster trafficking proteins. In E. coli, the monothiol glutaredoxin GrxD and the BolA-type proteins BolA and IbaG …

Mixed Quantum/Classical Theory Approach To Rotationally Inelastic Molecular Collisions Implemented On A Quantum Computer, Jonathan Andrade-Plascencia, Tamila Kuanysheva, Dulat Bostan, Brian K. Kendrick, Dmitri Babikov

Chemistry Faculty Research and Publications

All elements of a quantum algorithm for calculations of rotationally inelastic molecule + atom scattering within the framework of a mixed quantum/classical theory are outlined. In this approach, the rotational motion of the molecule is described quantum mechanically using the time-dependent Schrödinger equation, while the scattering process of two collision partners is treated classically. The matrix of potential coupling is precomputed on a classical processor, whereas the quantum hardware is used to propagate the system of coupled equations for the rotational state-to-state transitions. All quantum circuits needed for practical implementation of the algorithm are presented. First, the quantum codes written …

Quantum Simulation Of Molecular Dynamics Processes─A Benchmark Study Using A Classical Simulator And Present-Day Quantum Hardware, Tamila Kuanysheva, Brian K. Kendrick, Lukasz Cincio, Dmitri Babikov

Chemistry Faculty Research and Publications

We explore how the fundamental problems in quantum molecular dynamics can be modeled using classical simulators (emulators) of quantum computers and the actual quantum hardware available to us today. The list of problems we tackle includes propagation of a free wave packet, vibration of a harmonic oscillator, and tunneling through a barrier. Each of these problems starts with the initial wave packet setup. Although Qiskit provides a general method for initializing wave functions, in most cases it generates deep quantum circuits. While these circuits perform well on noiseless simulators, they suffer from excessive noise on quantum hardware. To overcome this …

Contextual Approach To Improve Problem Solving Skills In Ipas Subject At Elementary School: A Study Development Of Teaching Materials, Nur Hidayah, Sumarno Sumarno, Joko Siswanto

Jurnal Pendidikan Sains

The objective of this study is to assess the validity, practicality, and efficacy of instructional materials. We refer to this research as research and development, with a focus on the creation of teaching materials. The research design proposed by Borg and Gall consists of six steps: identification of potential and difficulties, data collecting, product design, design validation, design revision, and product trial. The utilized instruments comprise expert and practitioner validity sheets, teacher and student response surveys, and validation sheets for teaching materials and modules, as well as pretest and posttest questions. Experts performed the validity assessment, attaining a score of …

The Effort To Improve Students’ Problem-Solving Ability: Physics E-Modules For High School Students, Hidayatullah Hana Putra, Edi Supriana, Nasikhuddin Nasikhuddin, Annisa U. Yana, Suhailee Sohnui

Jurnal Pendidikan Sains

Physics teachers in Indonesia still face obstacles during learning, such as students who are less active and have difficulty in solving physics problems. The physics learning media used are also still not very interesting and are not based on authentic problem solving. Therefore, this study focuses on the development of PBL-based e-modules on work and energy to improve the physics problem-solving abilities of high school students. This research and development used the ADDIE design and was tested on 90 high school students in High School 1 Sumber Pucung Malang in the 2022/2023 academic year. The questionnaire instrument was used in …

Differentiated Teaching Module Using Problem Solving Model: Numerical Ability Of Elementary School Students, Risa Alifatin, Agus Sutono, Ida Dwijayanti

Jurnal Pendidikan Sains

This study aims to develop a differentiated teaching module using the problem-solving model that is valid, practical, and effective to improve students' numerical abilities. This study uses the ADDIE Model research and development approach. The sample in this study was class III of elementary school Tenggulangharjo as an experimental class totaling 22 students and class III of elementary school Karangtengah as a control class totaling 19 students. Data analysis used the t-test and N-Gain test. The study found that (1) the average validity score of the three parts of the Differentiated Teaching Module was 3.74, which is 93.62%, placing it …

Ethnoscience-Based Science Learning Through Composite Board Making Utilizing Eggshell Waste And Water Hyacinth Fiber (Eichornia Crassipes), Asep Khaidir Arpan, Yulia Sukmawardani, Pina Pitriana, Ade Yeti Nuryantini

Jurnal Pendidikan Sains

The demand for boards continues to increase every year, while overexploitation of wood leads to environmental degradation and forest loss. On the other hand, eggshell and water hyacinth waste continues to grow without optimal utilization. This research aims to make composite boards based on eggshell waste and water hyacinth fibers and analyze the potential of ethnoscience in science learning. This research used a qualitative descriptive method with a literature and documentation study approach. The materials used in this experiment are eggshell waste, water hyacinth fiber, and polyester resin. The composite board was made by mixing water hyacinth fiber and eggshell …

Analysis Of Students' Creative Thinking Skills In Learning Hydrocarbons By Using Daily Life-Based Practicum Method, Yenni Kurniawati, Laras Dyaz Handayani, Dea Ramadani, Nurhikmah Sari

Jurnal Pendidikan Sains

Creative thinking skill is a competence of the 21st century that is needed very much and needs to be increased by utilizing chemistry in life. This research aimed at analyzing student creative thinking skills in experimental and control groups and finding out the effect of the daily life-based practical work learning method on student creative thinking skills. This research was conducted in the eleventh grade at High School 1 Pekanbaru on the hydrocarbon lesson. The quasi-experimental method was used in this research with pretest-posttest and non-equivalent control group designs. The instruments used in this research were essay tests, observation, and …

Exploring Students’ Perceptions Of Science Laboratory Practices: A Comparative Study Between Rural And Urban Schools, Safrida Dwiningsih, Ina Lestari, Roma Ismi, Sri Wahyu Rahmadina, Masdalena Sinaga, M. Rahmad

Jurnal Pendidikan Sains

This study aims to analyze students' perceptions of the implementation of science laboratory practicums at public middle school 020 Pekanbaru and public middle school 7 Pangkalan Kuras, Riau Province. Using a quantitative survey method, this study involved 75 student respondents. The instrument used was a questionnaire consisting of 26 statements, analyzed descriptively. The results show that students' perceptions of the preparation, implementation, and conclusion stages of the practicum fall into the "good" category, with urban schools having a higher percentage. In conclusion, the implementation of practicums in urban schools is better than in rural schools, bringing attention to the need …

Digital Comic Learning Media (E-Comic) To Increase Student Learning Interest In Reaction Rate Material At High School, Berliana Afsohin Nabila, Achmad Lutfi

Jurnal Pendidikan Sains

This study aims to develop digital comic learning media that is effective in increasing students' interest in learning about reaction rate material, focusing on the media's validity, practicality, and overall effectiveness. This research utilizes the research and development method with the ADDIE model. Research instruments were used, including validity sheets to assess the media's validity, student activity observations, and student response questionnaires to evaluate the media's practicality, as well as student interest questionnaires and learning outcomes to measure the effectiveness of the learning media. The findings show that validity results showed a mode score of 4, indicating a very valid …

Teaching Materials Containing Kse To Support Character Education In Mathematics Subjects In Elementary Schools, Kunaenah Kunaenah, Rasiman Rasiman, Bagus Ardi Saputro

Jurnal Pendidikan Sains

The purpose of the study was to determine the validity, practicality, and effectiveness of teaching materials containing KSE to support character education in mathematics lesson content. This study employs a development research approach based on Borg and Gall's research design. The subjects of the study were in class V at public elementary school Kaliboyo. The data collection instruments used were validity sheets, response questionnaires, validation sheets, and observation sheets. The findings show that experts carried out the validity test, achieving a value of 93.30% in the very valid category. The practicality test results were derived from various sources: students' questionnaires, …

Development Of Differentiated Teaching Modules With A Scientific Approach To Improve Elementary School Students’ Science Literacy, Supriyanto Supriyanto, Joko Sulianto, Achmad Buchori

Jurnal Pendidikan Sains

The study aim is to determine the validity, practicality, and effectiveness of teaching materials. This type of research involves the development and creation of teaching module products. The research design used is ADDIE (Analysis, Design, Development, Implementation, Evaluation). The instruments used are validity sheets for experts and practitioners, teacher response questionnaires, teaching module validation sheets, and pretest and posttest questions. The findings show that experts conducted the validity test, achieving a score of 92.22 in the very valid category. The practicality test was obtained from the teacher questionnaire, which was stated as practical with an average value of 91.25, and …

Analysis Of Misconceptions In Learning Biology Mutation Material At High School, Fitri Hayati Kurnia, Tri Wahyu Agustina, Wahyuni Handayani

Jurnal Pendidikan Sains

This research aims to analyze student misconceptions regarding mutation material in class XII. The research method uses a descriptive approach with mixed methods, which combines qualitative and quantitative methods. Qualitative data was obtained through interviews with biology teachers, while quantitative data was obtained through questionnaires and essay tests on students. The research results indicate that the material that students like is growth and development, while the material they don't like is gene mutation and genetic material. Students' misconceptions occur due to preconception aspects, associative thinking, and a lack of understanding of genetic concepts. It was found that students' understanding of …

Vitamin D3 Toxicity-Induced Hypercalcemia In Staphylococcal Arthritis: A Focus On Il-6, Ali Jabbar Abd Al-Hussain Alkawaz, Maryam Sabah Naser, Ali Jalil Obaid, Zakaria M. Al-Ghazaly

Karbala International Journal of Modern Science

Background: Vitamin D3  over-supplementation can induce toxicity through the development of hypercalcemia and may disturb immune modulation. This study examines the relationship between hypercalcemia  resulting from Vitamin D3 Overdose and serum Interleukin-6 (IL-6) levels in patients diagnosed with staphylococcal arthritis.

Methods: Forty male patients (mean age: 31 years; range: 17–45 years) were enrolled from Dec. 2024 to Feb. 2025. Twenty cases of staphylococcal arthritis were compared with twenty healthy male controls. Serum concentrations of Vitamin D3, calcium, IL-6, and other biochemical markers (urea, creatinine, ESR, WBC, and potassium) were analyzed. Staphylococcus aureus was isolated from synovial fluid and confirmed using …

Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto

Journal of Electrochemistry

We introduce our state-of-the art of “vacuum consistent electrochemistry” to an investigation of the interfaces between oxides and ionic liquid (IL). Pulsed laser deposition (PLD) has been one of the powerful and sophisticated techniques to realize nanoscale preparation of high-quality epitaxial oxide thin films. On the other hand, electrochemistry is a simple, very sensitive, and non-destructive analysis technique for solid-liquid interfaces. To ensure the reproducibility in experiment of the interfaces of such epitaxial oxide films, as well as bulk oxide single-crystals, with IL, we employ a home-built PLD-electrochemical (EC) system with IL as an electrolyte. The system allows one to …

Pm Irras Studies Of Organized Molecular Films At A Gold Electrode Surface, Zhang-Fei Su, Ai-Cheng Chen, Jacek Lipkowski

Journal of Electrochemistry

This feature article illustrates the potential of polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) to provide molecular-level information about the structure, orientation and conformation of constituents of thin films at electrode surfaces. PM IRRAS relies on the surface selection rules stating that the p-polarized IR beam is enhanced, while the s-polarized beam is attenuated at the metal surface. The difference between p- and s-polarized beams eliminates the background of the solvent and provides IR spectra at a single electrode potential. In contrast, two other popular in situ IR spectroscopic techniques, namely, subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS) …

Redox-Active Monolayers On Ito Prepared By Post-Amidation And Direct Esterification And Their Spectroelectrochemical Characterization, Takamasa Sagara, Sae Nakai, Ryusuke Yofu, Shota Kojin

Journal of Electrochemistry

A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing. The necessity for its sophistication arises from the availability of multi-dimensional sensing signals. Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sensitivity and selectivity. This study aimed to elucidate the modification of an indium tin oxide (ITO) electrode with a viologen monolayer with an ordered orientation. Novel methods were developed to immobilize a viologen molecule bearing a carboxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide with N-hydroxy-succinimide (EDC/NHS). In the two methods …