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Comparing The Effects Of Project-Based Learning, Inquiry Learning, And Conventional Instruction On Students' Learning Motivation In Biology, Yeyen Angraini, Irwandi Irwandi, Jayanti Syahfitri Jun 2026

Comparing The Effects Of Project-Based Learning, Inquiry Learning, And Conventional Instruction On Students' Learning Motivation In Biology, Yeyen Angraini, Irwandi Irwandi, Jayanti Syahfitri

Jurnal Pendidikan Sains

Learning motivation is an important factor influencing students’ engagement, persistence, and success in Biology learning. However, classroom instruction at the senior high school level is often dominated by teacher-centered approaches, which may limit students’ active participation and motivational development. This study aimed to compare students’ learning motivation across Project-Based Learning (PjBL), Inquiry Learning, and conventional instructional approaches in Biology learning. The study employed a quantitative quasi-experimental design with a pretest–posttest approach involving three groups. Participants consisted of 85 Grade XI students from SMA Negeri 1 Talang Padang, South Sumatra, distributed across three classes: PjBL (n = 28), Inquiry (n = …


Distribution And Transport Of Lithium Ions At Interfaces Between Graphite And Carboxymethyl Celluloses, Zi-Jun Huang, Zhen-Ying Zheng, Hua-Wei Cao, Jian Wang, Qing-Feng Zhang, Sheng-Li Chen Jun 2026

Distribution And Transport Of Lithium Ions At Interfaces Between Graphite And Carboxymethyl Celluloses, Zi-Jun Huang, Zhen-Ying Zheng, Hua-Wei Cao, Jian Wang, Qing-Feng Zhang, Sheng-Li Chen

Journal of Electrochemistry

Carboxymethyl cellulose (CMC) is a water-processable binder widely used for graphite anodes. However, a microscopic understanding of why the identity of CMC counterions (Li+/Na+/K+) strongly affects electrode performance remains limited. Here, molecular dynamics (MD) simulations are used to track Li+ transport accessibility across electrolyte/CMC/graphite three-phase interfaces, comparing pure CMC-Li, CMC-Na, CMC-K, and mixed-counterion CMC binders. We find that CMC-Li sustains a continuous Li+ transport pathway from the electrolyte through the binder phase toward graphite. In contrast, in CMC-Na and CMC-K, Na+/K+ ions preferentially enrich at the graphite/binder interface, forming …


Using Low-Frequency Vibrational Spectroscopy To Develop Analytical Profiles For Polymorphic Organic Molecular Crystals, Salvatore Zarrella Jun 2026

Using Low-Frequency Vibrational Spectroscopy To Develop Analytical Profiles For Polymorphic Organic Molecular Crystals, Salvatore Zarrella

Dissertations - ALL

Low-frequency vibrational spectroscopy provides a sensitive approach for characterizing polymorphism and intermolecular dynamics in organic molecular crystals. Terahertz time-domain spectroscopy (THz-TDS) and low-frequency Raman spectroscopy probe collective lattice vibrations arising from weak intermolecular interactions, offering direct insight into crystal packing, phase stability, and structural organization that is often inaccessible to conventional diffraction and mid-infrared techniques. To interpret these modes, experimental measurements are combined with periodic solid-state density functional theory (ss-DFT), which enables vibrational assignments to specific intermolecular motions, and crystal structure prediction (CSP), which maps accessible polymorphic energy landscapes. Together, these methods form a unified experimental–computational framework for understanding molecular …


Peptide And Peptide Bioconjugate Based Drug Development For The Treatment Of Metabolic Diseases, Nancy Cham Jun 2026

Peptide And Peptide Bioconjugate Based Drug Development For The Treatment Of Metabolic Diseases, Nancy Cham

Dissertations - ALL

The Doyle group has coined the term ‘corrination’ to describe the conjugate modification of a peptide, protein, small molecule, or radionuclide with a corrin ring-containing molecule such as cobalamin, also known as vitamin B12 (B12), or cobinamides. By exploiting the innate chemico-physical properties of corrin ring-containing compounds, both in general and specifically via the innate dietary B12 uptake pathway in mammals, corrination has been explored for drug development and targeted/localized delivery of probes and therapeutics. Most recently, it is in the field of peptide-based therapeutics that corrination is generating significant interest, no doubt driven in part by the recent successes …


Molecular Identification Of Cryptococcus Albidus Isolated From A Gingivitis Infection In A Male From Karbala City, Iraq, Maysaa Taqi Al-Khazali, Zahraa Raheem Murshidy, Sarah Kadhim Al-Rahimy, Sura Abd Ali Kadhim Mohammed, Dhuha Ali Hussein Jun 2026

Molecular Identification Of Cryptococcus Albidus Isolated From A Gingivitis Infection In A Male From Karbala City, Iraq, Maysaa Taqi Al-Khazali, Zahraa Raheem Murshidy, Sarah Kadhim Al-Rahimy, Sura Abd Ali Kadhim Mohammed, Dhuha Ali Hussein

Karbala International Journal of Modern Science

The current study presents a case of gingivitis caused by Cryptococcus albidus in a 35-year-old male from the city of Karbala in Iraq. This fungal species was identified via morphology, microscopy, additionally to the VITEK system. C. albidus was further confirmed using the polymerase chain reaction (PCR) technique by amplifying the 18S rRNA gene as a universal primer and sequencing. Sequences analysis revealed that this strain of C. albidus had not been previously documented in the NCBI database. Hence, the newly obtained sequences were submitted to the GenBank repository and assigned the accession number OQ975882.1, marking the first report of …


Lafe0.925ti0.075o3 Perovskite Coated With Ethyl Cellulose: A High-Stability, Low-Hysteresis Platform For Advanced Humidity Sensing, Akhmad Futukhillah Fataba Alaih, Djoko Triyono, Rifqi Almusawi Rafsanjani Jun 2026

Lafe0.925ti0.075o3 Perovskite Coated With Ethyl Cellulose: A High-Stability, Low-Hysteresis Platform For Advanced Humidity Sensing, Akhmad Futukhillah Fataba Alaih, Djoko Triyono, Rifqi Almusawi Rafsanjani

Makara Journal of Science

Humidity sensors are pivotal in numerous sectors, such as environmental monitoring, industrial automation, and health-care. This study presents the fabrication and detailed evaluation of an advanced humidity sensor using ethyl cellulose (EC)-coated LaFe0.925Ti0.075O3 (LFTO) perovskite nanoparticles synthesized via the sol-gel method. The LFTO nanopar-ticles exhibited a mesoporous structure with an enhanced surface area, which significantly improved their moisture adsorption capabilities. The innovative application of EC coating addresses critical substrate adhesion issues, enhancing mechanical stability without compromising sensor sensitivity. Comprehensive performance evaluations revealed minimal hysteresis (


Laminarin-Loaded Solid-In-Oil Nanodispersion For Enhanced Non-Invasive Transdermal Immunization, Md. Shahin Ekka Sarker, Yoshirou Kawaguchi, Rie C. Wakabayashi, Noriho J. Kamiya, Muhammad Moniruzzaman, Masahiro Goto Jun 2026

Laminarin-Loaded Solid-In-Oil Nanodispersion For Enhanced Non-Invasive Transdermal Immunization, Md. Shahin Ekka Sarker, Yoshirou Kawaguchi, Rie C. Wakabayashi, Noriho J. Kamiya, Muhammad Moniruzzaman, Masahiro Goto

Publications and Research

Simple and non-invasive transdermal vaccination is an attractive alternative to conventional injection-based immunization. However, the effectiveness of transdermal vaccines is often constrained by the stratum corneum barrier. Although the use of solid-in-oil (S/O) nanodispersion technology has successfully facilitated skin permeation to induce an immunological response, the antibody titers remain suboptimal. Herein, a dectin-1 selective ligand, laminarin, was used as an immunostimulatory adjuvant to enhance the immune response. S/O nanodispersions loaded with laminarin and ovalbumin (OVA) were systematically developed and characterized in terms of particle size, in vitro OVA release behavior, and skin permeation performance using excised mouse skin. In vivo …


Knowledge, Attitude, And Practice Regarding Vitamin D Among Adults In Western Libya: Assessment And Socio-Demographic Influences, Abdounasser Albasher Omar, Kawther Adaila, Mofida M. Alfaid, Abdurrahman M Sweidan, Ruqayah Kasheem, Samia Emhemmed Abadi, Abdulnabi Ali Abushita, Hafsa A. Alemam Jun 2026

Knowledge, Attitude, And Practice Regarding Vitamin D Among Adults In Western Libya: Assessment And Socio-Demographic Influences, Abdounasser Albasher Omar, Kawther Adaila, Mofida M. Alfaid, Abdurrahman M Sweidan, Ruqayah Kasheem, Samia Emhemmed Abadi, Abdulnabi Ali Abushita, Hafsa A. Alemam

Al-Bahir

Vitamin D deficiency is a widespread public health concern, necessitating a clear understanding of knowledge, attitudes, and practices (KAP) among populations. Therefore, this study was conducted to assess Libyan citizens' knowledge, attitude, and practice (KAP) regarding vitamin D in the western region of Libya. This study was carried out between June and September of 2021. A questionnaire was distributed across the study area and the complete responses were 314, with 62.7% were females and 37.3% were males.  The scores were calculated as percentages and statistically tested. Additionally, the impact of some socio-demographic factors (age, gender, education level, job, and salary) …


Quantum Engineered Mxene–Graphene–Plasmonic Nanocomposites For Next-Generation Transparent And Flexible Space Photovoltaics, Arash Vaghef-Koodehi Jun 2026

Quantum Engineered Mxene–Graphene–Plasmonic Nanocomposites For Next-Generation Transparent And Flexible Space Photovoltaics, Arash Vaghef-Koodehi

Turkish Journal of Chemistry

This study presents a quantum‑engineered, tricomponent heterostructure comprising Ti3C2T MXene quantum dots (2–5 nm), single‑layer graphene, and plasmonic gold nanoparticles (15 ± 3 nm) uniformly embedded within electrospun polyacrylonitrile nanofibers. This integrated architecture demonstrates a remarkable combination of optical transparency (89.3 ± 1.1%) and power conversion efficiency (19.7 ± 0.4%) under AM0 solar illumination, representing 340% enhancement over state‑of‑the‑art transparent photovoltaic devices. A multiscale computational framework, bridging density functional theory and device‑level drift-diffusion modeling, identifies optimal interlayer spacing (3.4 ± 0.1 Å) as the key to achieving 89.3% charge‑transfer efficiency. Concurrently, localized surface plasmon resonances at 532 nm generate electromagnetic …


Efficient Heterogeneous Photo-Fenton Degradation Of Azo Dyes Using The Nanocomposite Mgfe2o4/Mos2, Zahra Zeinali, Leila Ershadi Afshar, Naz Chaibakhsh, Farnaz Isapour Jun 2026

Efficient Heterogeneous Photo-Fenton Degradation Of Azo Dyes Using The Nanocomposite Mgfe2o4/Mos2, Zahra Zeinali, Leila Ershadi Afshar, Naz Chaibakhsh, Farnaz Isapour

Turkish Journal of Chemistry

In the present work, a facile hydrothermal route was employed to synthesize the nanocomposite MgFe2O4/MoS2, which acted as a heterogeneous photo-Fenton catalyst for the degradation of a synthetic diazo dye, Acid Blue 113 (AB113). The nanocatalyst produced underwent analysis using multiple characterization techniques. The parameters influencing the oxidative reaction were statistically modeled and optimized using response surface methodology. Optimal degradation efficiency for AB113 (94.92%) was attained at pH 8.79 using 10 mg of MgFe2O4/MoS2 nanocatalyst, 1.6 mL of H2O2, and a reaction duration of 27 min. The synergistic effect resulting from the formation of electron-hole pairs renders the combined photocatalysis …


Electrochemical Biosensing Of Alpha-Fetoprotein Based On Carboxylated Multi-Walled Nanotube-Polyazur A (In Des)-Gold Nanoparticles, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç Jun 2026

Electrochemical Biosensing Of Alpha-Fetoprotein Based On Carboxylated Multi-Walled Nanotube-Polyazur A (In Des)-Gold Nanoparticles, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç

Turkish Journal of Chemistry

AFP, a cancer biomarker, is monitored during fetal development and in the serum of pregnant women. Sensitive and rapid monitoring of AFP is crucial for effective management. In this study, screen-printed carbon electrodes (SPCEs) modified with multi-walled carbon nanotubes (MWCNT-COOH), polyAzur A (PAA), which was prepared in a deep eutectic solution (DES), and gold nanoparticles (AuNP) were fabricated. AFP biosensors were developed for practical, sensitive, low-cost, and rapid detection of AFP. Optimizations of nanostructures (MWCNT-COOH, AuNP) and polymers (PAADES) were performed. The MWCNT-COOH, PAADES, and AuNP-modified SPCEs were characterized by FE-SEM-EDX, FTIR, and XRD techniques. The amounts of 6-MOH, APTES, …


Alcohol-Based Microextraction Of Rhodamine 6g From Soft Drink, Food, And Cosmetic Samples, Mustafa Soylak, Esra Yamaner, Özgür Özalp Jun 2026

Alcohol-Based Microextraction Of Rhodamine 6g From Soft Drink, Food, And Cosmetic Samples, Mustafa Soylak, Esra Yamaner, Özgür Özalp

Turkish Journal of Chemistry

By using alcohol-based solvent extraction without tetrahydrofuran, a liquid–liquid microextraction technique was developed for the separation–enrichment of trace levels of Rhodamine 6G from complex matrices, including soft drinks, food, cosmetics, hygiene products, and natural waters. Numerous experimental parameters were tuned, including pH, alcohol volume, ultrasonication time, and sample and eluent volume. The enrichment factor (EF), limit of detection (LOD), and limit of quantification (LOQ) were used to assess the analytical performance of the suggested approach. The LOD and LOQ were 6.92 ng mL−1 and 23 ng mL−1, respectively, and the EF was 14. Through the use of the standard addition …


A Modular Saponin Adjuvant Platform: Development, Structure–Activity Relationships, And Applications, Di Bai Jun 2026

A Modular Saponin Adjuvant Platform: Development, Structure–Activity Relationships, And Applications, Di Bai

ETDs from 2020-2029

ABSTRACT Saponin-based vaccine adjuvants have attracted considerable attention owing to the clinical success of QS-21, a potent immunostimulant capable of inducing balanced humoral and cellular immune responses, yet its widespread application is limited by supply constraints, chemical instability, and dose-dependent toxicity. To address these challenges, we previously developed two semisynthetic saponin adjuvants, VSA-1 and VSA-2, derived from abundant Momordica saponins through a single-step modification, which exhibit QS-21–comparable immunopotentiating activity with improved accessibility and stability. Here, we first performed a systematic structure–activity relationship (SAR) study of the VSA series using MS I as the lead scaffold. Modulation of the side-chain length …


A Nonenzymatic Electrochemical Glucose Sensor Depending On A Ninps/Co3o4/Functionalized Graphene Oxide-Modified Working Electrode, Sümeyra Pekmez, Muhammet Güler Jun 2026

A Nonenzymatic Electrochemical Glucose Sensor Depending On A Ninps/Co3o4/Functionalized Graphene Oxide-Modified Working Electrode, Sümeyra Pekmez, Muhammet Güler

Turkish Journal of Chemistry

In the present research, the aim was to develop a novel electrochemical enzyme-free glucose sensor dependent upon a nickel nanoparticles (NiNPs)/cobalt (II, III) oxide (Co3O4)/carboxylated graphene oxide (GO-COOH)-modified glassy carbon (GC) electrode. The electrocatalytic performance of the electrode was tested using various electrochemical methods such as amperometry and cyclic voltammetry (CV). The NiNPs@Co3O4/GO-COOH/GC electrode showed noticeably superior electrocatalytic behavior for glucose oxidation in 0.1 M NaOH media, ascribed to the good synergistic impact between NiNPs, Co3O4, and GO-COOH. The amperometric response of the NiNPs@Co3O4/GO-COOH/GC electrode to glucose exhibited two linear determination ranges at +0.55 V potential. The first one was …


Production, Purification, And Crystallization Of The Recombinant Her2 Tyrosine Kinase Domain (Her2-Tkd), Edanur Topalan, Hali̇li̇brahi̇m Çi̇ftçi̇, Hasan Demi̇rci̇ Jun 2026

Production, Purification, And Crystallization Of The Recombinant Her2 Tyrosine Kinase Domain (Her2-Tkd), Edanur Topalan, Hali̇li̇brahi̇m Çi̇ftçi̇, Hasan Demi̇rci̇

Turkish Journal of Chemistry

The human epidermal growth factor receptor 2 tyrosine kinase domain (HER2-TKD) is an important therapeutic target in oncology. In this study, we developed a practical and cost-effective approach for producing soluble recombinant HER2-TKD in Escherichia coli as a basis for structure-based drug discovery. The gene encoding HER2-TKD was cloned into a pET28a(+) expression vector and expressed in E. coli. Since the protein was initially obtained as inclusion bodies, solubilization with 1.5% sarcosyl was applied to recover it in soluble form. The purified protein was obtained through size-exclusion chromatography, followed by tag removal using reverse affinity purification. Crystallization trials were performed …


Data-Driven Electrochemistry Reveals The Impact Of Hydrophobicity On Aptamer Cross-Reactivity, Emily Carroll, Michael A. Pence, Elizabeth Winterholler, Taylor D. Sparks, Shelley D. Minteer Jun 2026

Data-Driven Electrochemistry Reveals The Impact Of Hydrophobicity On Aptamer Cross-Reactivity, Emily Carroll, Michael A. Pence, Elizabeth Winterholler, Taylor D. Sparks, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Electrochemical aptamer-based (E-AB) biosensors offer a promising platform for reagentless detection of molecular targets, yet aptamer recognition can be limited by cross-reactivity, particularly for hydrophobic analytes such as steroid hormones. To investigate how cross-reactivity influences E-AB sensor performance, we use automation and machine learning to screen a library of possible interferent molecules against a steroid-binding aptamer, with progesterone serving as a physiologically relevant test case. Here, we develop a label-free E-AB sensor for progesterone detection using a methylene blue-modified aptamer anchored with a hexanethiol linker. We then used an automated electrochemistry platform to perform reproducible and high-throughput characterization of our …


Main-Chain Ion-Pair Polybenzimidazole Membranes Enabling Reduced-Temperature Ht-Pemfc Operation (Down To 120°C), Brian C. Benicewicz, Huina Lin Jun 2026

Main-Chain Ion-Pair Polybenzimidazole Membranes Enabling Reduced-Temperature Ht-Pemfc Operation (Down To 120°C), Brian C. Benicewicz, Huina Lin

Faculty Publications

Proton exchange membrane (PEM) fuel cells are promising for clean and efficient energy conversion across diverse applications. High-temperature PEM fuel cells (HT-PEMFCs) using phosphoric acid (PA)-doped polybenzimidazole (PBI) can operate up to 200°C, but at lower temperatures, water-induced PA loss often leads to performance degradation and reduced durability. In this work, we present a new class of main-chain ion-pair PBI membranes by integrating the imidazolium-biphosphate ion-pair units directly into the PBI backbone. This design results in membranes with high acid content, stronger acid-polymer interactions and stabilized acid retention. In single-cell tests, the Im+-PBI15-3 wt.% exhibits peak power densities of 0.79 …


High-Throughput Optical Analysis To Inform Design Of Electrochemical Biosensors, Nathan J. Ricks, Michael A. Pence, Monica Brachi, Shelley D. Minteer Jun 2026

High-Throughput Optical Analysis To Inform Design Of Electrochemical Biosensors, Nathan J. Ricks, Michael A. Pence, Monica Brachi, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Electrochemical biosensors are central to wearable diagnostics, point-of-care testing, and continuous health monitoring due to their low power requirements, compatibility with miniaturized electronics, and proven clinical impact. Despite these advantages, the development of new electrochemical biosensors remains slow, constrained by limited throughput, complex electrode–biomolecule interfaces, and challenges associated with selectivity and performance in chemically complex environments. This perspective outlines how the next generation of electrochemical biosensors can be enabled by decoupling high-throughput front-end discovery and optimization from electrochemical readouts using nonelectrochemical surrogate assays. Optical, affinity, and cell-sorting platforms, including SELEX, fluorescence-activated cell sorting, and chemically coupled fluorescence assays, allow orders-of-magnitude …


The Effect Of Project-Based Learning Model On Entrepreneurship (Pjbl-E) With A Deep Learning Approach On Students' Problem-Solving And Cognitive Skills, Ricce Oktasari, Irwandi Irwandi, Siti Darwa Suryani Jun 2026

The Effect Of Project-Based Learning Model On Entrepreneurship (Pjbl-E) With A Deep Learning Approach On Students' Problem-Solving And Cognitive Skills, Ricce Oktasari, Irwandi Irwandi, Siti Darwa Suryani

Jurnal Pendidikan Sains

This study aims to examine the effect of the Entrepreneurship-based Project Based Learning (PjBL-E) model integrated with a pedagogical Deep Learning approach on students’ problem-solving skills and cognitive learning outcomes in biology learning. The novelty of this study lies in the integration of entrepreneurship values and pedagogical deep learning principles into Project Based Learning to create contextual and meaningful learning experiences. Entrepreneurship integration encourages students to develop innovative products, identify real-world problems, and apply biological concepts in practical and socio-economic contexts. Meanwhile, the pedagogical Deep Learning approach promotes reflective thinking, conceptual understanding, critical analysis, and the ability to connect theory …


Student Worksheets Based On The Local Wisdom Of Besilek Serawai For Sixth-Grade Elementary Science Learning, Mice Agustin, Tomi Hidayat, Irwandi Irwandi Jun 2026

Student Worksheets Based On The Local Wisdom Of Besilek Serawai For Sixth-Grade Elementary Science Learning, Mice Agustin, Tomi Hidayat, Irwandi Irwandi

Jurnal Pendidikan Sains

This study aims to develop a Student Worksheet (Lembar Kerja Peserta Didik [LKPD]) based on the local wisdom of Besilek Serawai for sixth-grade elementary science education and to evaluate its validity. The study employed the ADDIE development model, consisting of five stages: Analyze, Design, Develop, Implement, and Evaluate. The developed LKPD integrates Besilek Serawai, a traditional martial art of the Seluma community, with the concept of the human locomotor system in science instruction. The worksheet was validated by two subject-matter experts and two media experts. Material validation yielded an average score of 4.26, equivalent to a validity percentage of 85.2%, …


Extraction Of High-Quality Cashew Nutshell Liquid Using Carbon Dioxide-Expanded Hexane, Frank N. Jacob, Neema Msuya, Joseph Y.N Philip, Kando Khalifa Janga Jun 2026

Extraction Of High-Quality Cashew Nutshell Liquid Using Carbon Dioxide-Expanded Hexane, Frank N. Jacob, Neema Msuya, Joseph Y.N Philip, Kando Khalifa Janga

Tanzania Journal of Science

Cashew nutshell liquid (CNSL) is a by–product from cashew processing industries containing four naturally occurring phenolic compounds. This study investigated an extraction approach using CO2–expanded hexane. The central composite design (CCD) was employed in experimental design to investigate the effects and interaction of CO 2 mole fractions and extraction temperature on the CNSL yield and quality (Colour) from Steamed CNSL. The dissolution power of the CO2–expanded hexane was assessed by determining the solubility of CNSL during the initial stages of extraction at different extraction conditions. Findings indicated that higher CO2 mole fractions reduced CNSL solubility, while higher temperatures enhanced it. …


Antioxidant Potential Of A Non-Heme Iron Complex: Mitigating H2O2-Induced Cellular Damage, Magy A. Mekhail, David M. Freire, Cameron Bowers, Grant Elam, Nora Del Bosque, Hannah K. Pyle, Sarah K. Dunn, Spencer Lanyon, Timothy J. Hubin, Giridhar Akkaraju, Kayla N. Green Jun 2026

Antioxidant Potential Of A Non-Heme Iron Complex: Mitigating H2O2-Induced Cellular Damage, Magy A. Mekhail, David M. Freire, Cameron Bowers, Grant Elam, Nora Del Bosque, Hannah K. Pyle, Sarah K. Dunn, Spencer Lanyon, Timothy J. Hubin, Giridhar Akkaraju, Kayla N. Green

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Iron complexes with antioxidant activity have garnered significant interest for both general and medical applications, yet few studies have yielded functional nonheme iron-based mimics for H2O2 mitigation in aqueous environments. Here, we investigate water-soluble nonheme iron complexes derived from 12-membered pyridinophanes (CF3PyN3, PyN3, NMe2PyN3, and Py2N2) to evaluate the impact of ligand scaffolds on H2O2 decomposition activity both in vitro and in a cellular model. Speciation and kinetic analyses reveal that both electronic and geometric modulation of the macrocyclic …


Engineering Nanoelectrocatalytic Systems For Co2 And Nitrate Conversion Into Value-Added Chemicals, Abdelrahman Mohamed Abdelmohsen Jun 2026

Engineering Nanoelectrocatalytic Systems For Co2 And Nitrate Conversion Into Value-Added Chemicals, Abdelrahman Mohamed Abdelmohsen

Theses and Dissertations

The thesis addresses two major related environmental crises: nitrate pollution of water systems and the ever-increasing levels of atmospheric carbon dioxide. Both challenges are closely linked to anthropogenic disturbance of nitrogen and carbon cycles and require sustainable, energy efficient mitigation techniques. In this study, we investigate electrochemical conversion routes as a unified approach to convert these pollutants into value-added compounds: ammonia (NH3) via nitrate reduction (NO3-RR) and ethylene (C2H4) via carbon dioxide reduction (CO2RR). The first half of this work deals with the design and engineering of Cu-Zn alloy electrocatalysts for efficient NO3-RR. Tuning the alloy composition and surface nanostructure …


Refining A Flow Injection Analysis Method For Trace Concentrations Of Iron In Seawater, Brooke I. Stafford, Liam W. Hodgson, Noah S. Schuhmann, Elijah J. Vestal, Claire P. Till Jun 2026

Refining A Flow Injection Analysis Method For Trace Concentrations Of Iron In Seawater, Brooke I. Stafford, Liam W. Hodgson, Noah S. Schuhmann, Elijah J. Vestal, Claire P. Till

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Iron is an essential micronutrient required for the growth of phytoplankton, the base of the oceanic food chain. Iron exists in the ocean in extremely low concentrations, limiting primary productivity in ~⅓ of the surface ocean, and can be affected by physical processes such as upwelling of water masses, and by biological and chemical processes within the water. In order to further our understanding of iron availability in the ocean, here we refine and improve our understanding of an analytical method to measure nanomolar iron in seawater. The method used is an adaptation of Lohan et al. (2006), a flow …


Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio Jun 2026

Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Enzyme kinetics is a powerful technique used to quantify the rate at which an enzyme converts a substrate into a product and to identify potential inhibitors. In this study, kinetic analysis was employed to assess the activity of yeast alcohol dehydrogenase (YADH) in the presence and absence of sweeteners commonly found in alcoholic beverages. YADH catalyzes the oxidation of ethanol to acetaldehyde using NAD⁺ as a cofactor; the reduction to NADH can be monitored spectrophotometrically at 340 nm. Based on structural similarities to the ribose moiety of NAD⁺, it was hypothesized that sucrose and sucralose could directly interact with the …


Unraveling The Nanoscopic Characteristics Of The Heterogeneous Deep Eutectic Solvent Formed By Lauric Acid And N-Methylacetamide: An Experimental And Computational Approach, Laura X. Sepulveda Jun 2026

Unraveling The Nanoscopic Characteristics Of The Heterogeneous Deep Eutectic Solvent Formed By Lauric Acid And N-Methylacetamide: An Experimental And Computational Approach, Laura X. Sepulveda

LSU Doctoral Dissertations

Deep eutectic solvents (DESs) are attractive systems for extraction and separation of compounds. One example of this is the DES formed by the combination of lauric acid (LA) and N-methylacetamide (NMA), system that has been shown to efficiently separate oil/water mixtures through gel formation between LA and oil molecules. Structural characterization of this system using small-angle X-ray scattering (SAXS) and vibrational spectroscopy revealed the existence of nanometer-scale LA domains embedded in a continuous polar NMA phase, where LA and NMA interact through hydrogen bonding. These LA domains are responsible for the separation efficiency of linear organic molecules. However, this DES …


Uranyl Complex Of 1,3-Bis(Ditertbutylphosphinoxidomethyl)Benzene, Maha M. Alotaibi, Md Abdul Goni, Eric Reinheimer, Tasneem A. Siddiquee Jun 2026

Uranyl Complex Of 1,3-Bis(Ditertbutylphosphinoxidomethyl)Benzene, Maha M. Alotaibi, Md Abdul Goni, Eric Reinheimer, Tasneem A. Siddiquee

Chemistry Faculty Research

This short note presents a new molecule isolated and characterized from the reaction of uranyl nitrate with the PCP-type pincer ligand 1,3-bis(ditertbutylphosphinomethyl)benzene in the presence of UV light under ambient conditions. The new dinuclear uranyl-PCP complex was characterized by using FT-IR spectroscopy and single-crystal X-ray crystallography. As revealed by the crystal structure, the new complex had oxygen atoms coordinating from the phosphinoxides that were oxidized under ambient conditions. Each uranium atom of this dinuclear complex was found to exhibit pentagonal bipyramidal coordination geometry.


Structure And Spectroscopy Of Free Base, Copper, And Zinc Tetrapentylporphyrin, Christopher J. Ziegler, Nneka Damola Ajayi, Victor N. Nemkyin, G Richard Geier Iii Jun 2026

Structure And Spectroscopy Of Free Base, Copper, And Zinc Tetrapentylporphyrin, Christopher J. Ziegler, Nneka Damola Ajayi, Victor N. Nemkyin, G Richard Geier Iii

University Research

Synthetic porphyrins have been crucial as models for heme units and other biological porphyrins, as well as components of advanced materials and catalysts. Much of the work on synthetic porphyrins has focused on the meso-substituted 5,10,15,20-tetraphenylporphyrin (TPP) or the pyrrole-substituted 2,3,7,8,12,13,17,18-octaethylporphyrin (OEP). In this report, we present a comprehensive spectroscopic, electrochemical, and computational study of free-base, zinc(II), and copper(II) 5,10,15,20-tetrapentylporphyrin (TPeP). TPeP can be prepared via a two-step, one-flask reaction of pyrrole and hexanal mediated by Montmorillonite K10, followed by oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in yields of around 40%. Similar to TPP, the TPeP systems have the highest occupied molecular …


Structure And Spectroscopy Of Free Base, Copper, And Zinc Tetrapentylporphyrin, Christopher J. Ziegler, Nneka Damola Ajayi, Victor N. Nemkyin, G Richard Geier Iii Jun 2026

Structure And Spectroscopy Of Free Base, Copper, And Zinc Tetrapentylporphyrin, Christopher J. Ziegler, Nneka Damola Ajayi, Victor N. Nemkyin, G Richard Geier Iii

University Research

Synthetic porphyrins have been crucial as models for heme units and other biological porphyrins, as well as components of advanced materials and catalysts. Much of the work on synthetic porphyrins has focused on the meso-substituted 5,10,15,20-tetraphenylporphyrin (TPP) or the pyrrole-substituted 2,3,7,8,12,13,17,18-octaethylporphyrin (OEP). In this report, we present a comprehensive spectroscopic, electrochemical, and computational study of free-base, zinc(II), and copper(II) 5,10,15,20-tetrapentylporphyrin (TPeP). TPeP can be prepared via a two-step, one-flask reaction of pyrrole and hexanal mediated by Montmorillonite K10, followed by oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in yields of around 40%. Similar to TPP, the TPeP systems have the highest occupied molecular …


Synthesis And Characterization Of Organometallic Polymers And Their Cytotoxicity Towards Human Cancer Cell Lines, Paul Peter Slawek Jun 2026

Synthesis And Characterization Of Organometallic Polymers And Their Cytotoxicity Towards Human Cancer Cell Lines, Paul Peter Slawek

Electronic Theses and Dissertations

This research aimed to synthesize organometallic polymers from dialkyl (methyl, ethyl, butyl, cyclohexyl, and octyl) and diaryl (phenyl) tin dichlorides and three organic monomers, dipicolinic acid (DPA), chloramphenicol (CH), and isomannide (IS), using interfacial polymerization. Structure-activity relationships were investigated through physicochemical characterization (light-scattering photometry, proton NMR, and IR spectroscopy) and cytotoxicity was evaluated against six human cancer cell lines (AsPC-1, PANC-1, MCF-7, MDA-MB-231, HT-29, PC-3), with cisplatin serving as the reference standard.

Five DPA/tin polymers were synthesized, with IC50 values in the range of 0.60–0.71 μg/mL. Their cytotoxicity was significantly lower than that of cisplatin (0.0023-0.044 μg/mL), suggesting that …