Chemistry Commons^™

Synthesis And In Vitro Evaluation Of Potential Tuberculosis Antibiotics, Chloe Spradlin

Honors Projects

Tuberculosis (TB) remains a major global health threat. The bacteria causing TB, Mycobacterium tuberculosis, has proven difficult to combat, as drug resistance (MDR-TB) continues to develop within the bacteria. Access to healthcare in developing countries complicates the treatment of TB and MDR-TB. The World Health Organization has declared TB a global health crisis and has called for the development of new therapies. Previously, we used AutoDock Vina software to design novel drugs targeting InhA, an enzyme involved in mycobacterial cell wall synthesis. This project focuses on synthesizing amino diphenyl amides (ADA) and screening them against Mycobacterium. The synthetic pathway enables …

Designing Surface-Induced Entatic States In Copper Complexes For Tunable Reactivity, Rachel Kiser

Senior Theses

Copper catalysts play an important role in electrocatalytic oxidation reactions due to their redox flexibility and relative abundance compared to noble metal catalysts. In biological systems, copper metalloenzymes often achieve enhanced reactivity through an entatic state. Entasis is described as an active site or metal center being constrained to a geometric and electronic state, minimizing primary sphere reorganization energy and achieving higher rates of electron transfer.  This study investigates whether entasis can be achieved in synthetic molecular catalysts by immobilizing Cu(I) complexes onto metal oxide surfaces. Two Cu(I) complexes bearing carboxylate-functionalized ligands were examined both in homogeneous solution and when …

Crystallization And Utility Of Brominated Phenylethynylene Bis-Urea Macrocycles, Paras Srivastava

Senior Theses

Macrocycles are large, cyclic molecules with central cavities that can encapsulate other molecules and that have uses in supramolecular chemistry. The Shimizu group has previously synthesized Macrocycle 1, a phenylethynylene bis-urea macrocycle that crystallizes in a columnar form, enabling its utility as a host in host-guest systems. Reactions within these systems can be used to modify stereospecificity, kinetics, and other physical properties. Previously, photodimerization reactions between coumarins and chromones have been studied in systems of Macrocycle 1, resulting in the improved specificity of photodimerization products. Herein, we apply a dynamic covalent chemistry (DCC) strategy to synthesize Macrocycle 1 and its …

Increased Backbone Rigidity Of Artificial Transcription Factors, Jasmine Glover, Emma Otey, Joanna K. Kwao, Nicholas Truex

Senior Theses

Programming DNA-binding proteins is an effective strategy for developing therapeutics that regulate gene expression. These proteins can directly bind to DNA to activate or repress transcription of specific genes. Zinc finger proteins are a class of DNA-binding proteins commonly found in eukaryotic organisms. Their DNA-binding function is derived from unique amino acid sequences within each domain that recognizes specific nucleotides, allowing each finger to selectively recognize three DNA base pairs. Adjoining of multiple domains in tandem allows recognition of a specific DNA sequence. Artificial transcription factors can be made of multiple zinc finger domains arranged in tandem and engineered to …

Synthesis And Characterization Of Metal Complexes Of Oxindole-Based Β-Lactams, Kenya Rosas, Erick Morales Orrante, Carlos Sifuentes, Alexsei Nazarov

Posters - 2026

• β-lactams are essential structural components of many antibiotics and widely studied due to their biological importance and synthetic versatility.
• The Ugi reaction is a multicomponent reaction, involving a primary amine, carboxylic acid, isocyanide, and an aldehyde or a ketone, that rapidly generates α-acetamido carboxamide derivatives (Ugi adducts).
• The synthesis and characterization of four oxindole-based β-lactam derivatives:
  • 1-Benzyl-N-(tert-butyl)-2-oxo-3-(2-oxoazetidin-1-yl)indoline-3-carboxamide (4a).
  • N-(tert-butyl)-2-oxo-3-(2-oxoazetidin-1-yl)-1-phenylindol-3-carboxamide (4ab).
  • N-(tert-Butyl)-2-oxo-3-(2-oxoazetidin-1-yl)indoline-3-carboxamide (4d).
  • N-(tert-butyl)-1-methyl-2-oxo-3-(2-oxoazetidin-1-yl)indol-3-carboxamide (4e).
• The coordination of the four Ugi adducts with Cu (II) and Ni (II) at different pH points to enhance their stability and improve biological activity.

Quantifying Nutrient Fluxes Across The Sediment-Water Interface In The Lafayette River Estuary, Adriana E. Amrhein

OES Theses and Dissertations

The Lafayette River, a shallow, eutrophic tributary of the Chesapeake Bay, experiences seasonal harmful algal blooms (HABs). While management efforts focus on reducing external nutrient inputs, internal loading from benthic sediments remains poorly constrained. This study quantifies spatial and seasonal variability in nutrient and radium isotope fluxes across the sediment–water interface at three sites where HABs are known to initiate and represent contrasting sediment textures and hydrodynamic conditions. Sediment cores and porewater samples were collected in summer 2023 and winter 2024 to measure grain size, porosity, dissolved nutrients (NH₄⁺, NOₓ⁻, PO₄³⁻), and radionuclide activities (²²⁴Ra and ²²⁸Th). Radium isotope disequilibrium …

Biocrude From Organic Waste And Its Conversion To Hard Carbon: Experimental And Modeling Study, Isamu Umeda

Civil & Environmental Engineering Theses & Dissertations

This study establishes a technical and theoretical foundation for the efficient conversion of organic waste into biocrude and high-value carbon materials, aiming to facilitate the industrialization of hydrothermal and solvothermal liquefaction. The dissertation research is structured as follows:

Chapter 2 developed a novel chemical kinetic model for the HTL of corn stover based on elemental balances (C, H, N, and O). By incorporating temperature, residence time, solid loading as an independent variable, the model successfully predicted product yields and properties, revealing that there was non-pseudo-first-order reaction pathways in the conversion of water soluble organics in aqueous phase (AP) to hydrochar. …

Observations Of An Oscillatory Mechanochemical Reaction Between Tetrathiafulvalene And Chloranilic Acid, Alastair Deans

Physics Theses & Dissertations

Mechanochemistry is the study of chemical reactions driven by the input of mechanical en ergy in addition to thermal activation. Mechanochemical reactions from powders are carried out by manual grinding or milling using various types of ball mills, or in twin extruders. While mechanochemistry has great potential affording economically and environmentally advantageous “green” synthetic methods, a drawback is that its chemical mechanisms are not well understood. One example of such a reaction currently under study involves tetrathiafulvalene, an organic elec tron donor with two polymorphs (orange and brown), and chloranilic acid, an electron acceptor. Previous results show that neat grinding …

Radicals Transforming Organic Matter: Implications For Non-Pyrogenic Black Carbon And Nitrogen Formation, Molecular Dynamics In Tropical Soils, And Lignin Valorization, João Vitor Dos Santos

Chemistry & Biochemistry Theses & Dissertations

Radicals drive the transformation of organic matter in natural and engineered systems, altering its structure, reactivity, and stability. Condensed aromatic carbon (ConAC) and condensed aromatic nitrogen (ConAN) are among the most persistent forms of organic matter in soils and are traditionally interpreted as products of biomass burning. This dissertation challenges the long-standing assumption that these materials are exclusively pyrogenic, showing that iron-mediated radical chemistry can generate condensed aromatic structures under ambient conditions.

Chapters II and III show that Fenton-like radical oxidation of lignin-rich biomass produces condensed aromatic structures compositionally similar to pyrogenic black carbon and black nitrogen when assessed with …

Toxicity, Chemistry, And Public Health Relevance Of Emerging Nicotine Analog Vapes, Pods, And Pouches., Rhea Raghu, Mohana Sengupta, Karen Lin, Felix Effah, Robert M. Strongin, Irfan Rahman

Chemistry Faculty Publications and Presentations

Electronic nicotine delivery system manufacturers, such as Charlie's Holdings Inc., ECBlend, Outlaw, and NicRiver, have recently introduced nicotine analogs, such as 6-methyl nicotine, 6-MN ("Metatine"), and nicotinamide, NA ("Nixamide," "Nixodine," or "Nixotin-free base and salt") in products to circumvent the U.S. FDA's premarket tobacco product application (PMTA) requirements. Marketed as "tobacco-free," "PMTA-exempt," or "FDA-approved," these compounds now appear in oral nicotine pouches and disposable bars/vapes from brands such as Outlaw Dip, Kumi-Six, SBX, Katchmi, and Spree Bar under proprietary labels including "NoNic6," "Metatine," or "NIC-SAFE." These products often mimic the appeal of conventional nicotine delivery systems, with extensive use of …

Preferences For Mathematics And Science Education Majors Among Senior High School Students In Bataan, Zydrick L. Avelino

Jurnal Pendidikan Sains

This study examines the factors influencing Senior High School students’ preferences for Bachelor of Secondary Education (BSEd) majors in Bagac and Morong, Bataan, with particular focus on the low interest in Mathematics and Science specializations despite increasing demand for STEM educators. Using a descriptive quantitative design, data were collected from 369 students through a structured survey and analyzed using frequency and percentage distributions. The results reveal a strong preference for non-STEM majors, with Social Studies (42.12%) and English (35.04%) dominating, while Science (15.43%) and Mathematics (7.395%) received significantly lower interest. Personal interest emerged as the primary determinant (58.8%), followed by …

Design And In Silico Modeling Of Heterocyclic-Based Xanthone Derivatives As Potential Anticancer Agents Through Tyrosine Kinase Inhibition, Yehezkiel Steven Kurniawan, Ervan Yudha, Nela Fatmasari, Radite Yogaswara, Harno Dwi Pranowo, Eti Nurwening Sholikhah, Jumina Jumina

Makara Journal of Science

Cancer is one of the deadliest diseases nowadays, and tyrosine kinase receptors play crucial roles in cancer cell survival, differentiation, proliferation, and migration. This study designed and developed a new inhibitor from heterocyclic-based xanthone derivatives to target two tyrosine kinase receptors, epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor (PDGFR), through in silico screening. Eighteen heterocyclic-based xanthones were evaluated through molecular docking for both receptors. All heterocyclic-based xanthones gave the root mean square deviation (RMSD) value lower than 2.00 Å. Xanthone with isobenzothiazole substituent (iBzThio) was found as the most potent inhibitor with binding energies of -10.60 and …

Anthrone-Based Dummy Molecularly Imprinted Polymer For The Selective Detection Of Fluorene And Phenanthrene In Simulated River Water, Aria Pinandita, Nurrahmi Handayani, Muhammad Iqbal, Untung Triadhi, Rusnadi Rusnadi, Samitha Dewi Djajanti, Muhammad Bachri Amran, Muhammad Ali Zulfikar

Makara Journal of Science

A dummy-template molecularly imprinted polymer (DMIP) was synthesized via precipitation polymerization using anthrone as a template analog for the selective analysis of low-molecular-weight polycyclic aromatic hydrocarbons (PAHs), specifically fluorene and phenanthrene. Styrene, benzoyl peroxide, and ethylene glycol dimethacrylate were employed as the functional monomer, radical initiator, and crosslinking agent, respectively. The synthesized polymers were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and particle size analysis. The imprinting factors were 1.16 and 1.09 for fluorene and phenanthrene, respectively, indicating enhanced affinity of the imprinted sites. High-performance liquid chromatography analysis following DMIP-based solid-phase extraction yielded recoveries of 91.49% ± 3.87% for …

A Ferrocene-Modified Carbon Electrode Prepared From Coconut Shell Char For Cu(Ii) Detection In Water, Nabila Putri Aulia, Fitria Rahmawati, Abu Masykur, Eddy Heraldy

Makara Journal of Science

A ferrocene (Fc)-modified carbon electrode was prepared from coconut shell char (CSC), which was activated with NaOH to produce an activated coconut shell carbon (Ac-CSC). The carbon electrode was designed as a printed-carbon electrode consisting of working, counter and reference electrodes in a single piece, called a screen-printed carbon electrode, or SPCE. An Fc solution was applied to the working electrode part at 10%, 20% and 30% mass of the SPCE, producing an SPCE-Fc as an electrochemical sensor for Copper ions Cu(II) detection. The prepared activated carbon was analysed by XRD, FTIR, SEM/EDX, surface area analysis and impedance measurement to …

Axial Sulfur-Coordination Engineering Boosting Fe–N–C Catalysts For High-Performance Proton Exchange Membrane Fuel Cells, Lin Lin, Xiu-Xuan Hou, Zhe-Chen Fan, Yi-Xuan Yin, Wei-Yi Zhao, Kai Wei, Yu-Die Zhou, Li-Na Hou, Ying Wang, Hao Wan, Jun-Jie Ge

Journal of Electrochemistry

Fe-N-C catalysts have long suffered from kinetically sluggish oxygen reduction reaction (ORR) due to excessive adsorption strength toward oxygen intermediates and low site utilization. Heteroatom doping effectively accelerates ORR reaction kinetics through electronic structure modulation of metal sites for optimal intermediate adsorption, while chemical vapor deposition (CVD) enhances the turnover frequency (TOF) of active sites. Herein, we developed an FeSNC catalyst featuring abundant FeS₁N₄ sites via a dual-precursor CVD strategy. Experimental and theoretical analyses revealed that S incorporation disrupts the symmetric coordination of active sites, which optimizes OH* adsorption energies from 0.212 eV to 1.194 eV. Moreover, …

Deciphering The Role Of Binder Reaction Exothermicity In Thermal Runaway Of Lithium-Ion Cells, Wen Wen, Jing-Hong Zhou, Hao-Tian Lu, Xing-Gui Zhou

Journal of Electrochemistry

Thermal safety associated with lithium-ion cells as power sources remains a critical industry concern. A comprehensive understanding of how internal exothermic side reactions contribute to temperature rise is fundamental for accurately analyzing thermal runaway processes and predicting the thermal safety of lithium-ion cells. While various side-reactions, such as decomposition of solid electrolyte interphase layer, reaction between anode materials and electrolyte, reaction between cathode materials and electrolyte, and electrolyte decomposition, have been identified as heat generation sources in previous studies, the quantification of these reactions remains insufficiently standardized. Particularly, the impact of heat generation from binder decomposition (most commonly polyvinylidene difluoride) …

Entropy Of Metal/Solution Interfaces: Thermodynamic Framework, Theoretical Models, And Roles Of Interfacial Water, Zeng-Ming Zhang, Zi-Xi Liang, Jun Huang

Journal of Electrochemistry

Entropy is a basic thermodynamic property of the electrical double layer (EDL) at metal/solution interfaces, yet, its definition, measurement, and theoretical treatment are dispersed in the literature, and, in some cases, ambiguous. In this paper, we revisit the thermodynamic theory of EDL, from which two variants of entropy, excess entropy and formation entropy, are obtained and compared. In terms of the formation entropy, two calculation routes are validated in the context of a primitive EDL model, namely, the Gouy-Chapman (GC) model. After clarifying the concepts and calculation routes, we investigate interfacial water effects on the EDL entropy, using a refined …

Design, Synthesis, And Bioevaluation Of Moxifloxacin Hydrazide Metal Complexes: Integrated Spectroscopic, Computational, Antimicrobial, And Anticancer Investigations, Abbas Mamdoh Abbas, Sara Reda Fisal, Ibrahim A.I. Ali, W. Christropher Boyd, Haitham F. Kalil, Adel Sayed Orabi

Chemistry Faculty Publications

This study reports the synthesis, spectroscopic characterization, and biological evaluation of a novel moxifloxacin hydrazide derivative (MOX-H) and its metal complexes with Co(II), Ni(II), Cu(II), VO(IV), and Gd(III). The ligand was synthesized by hydrazinolysis of moxifloxacin hydrochloride, and the resulting hydrazide was subsequently complexed with the respective metal salts. The interaction between MOX-H and the metal ions yielded the corresponding complexes, formulated as [Co(H2O)Cl(MOX-H)2]Cl & centerdot;2.5H2O, [Ni(H2O)Cl(MOX-H)2]Cl.4.5H2O, [VO(MOX-H)2]SO4.3.5H2O, [Gd (H2O)(MOX-H)2(NO3)2]NO3.2H2O, and [Cu(MOX-H)2(H2O)Cl]Cl & centerdot;xH2O (where x = 2, 2.5, 0.5, for products synthesized via template, microwave-assisted, and hydrothermal methods, respectively). The synthesized analogues were characterized by elemental analysis (CHN), FT-IR, …

Interview With Orca Award Winner David Hage, Unl Chemistry; Drug-Protein Interactions, Mark Griep, David Hage

UNL ORCA Interview Series

Prof. David Hage was awarded the ORCA in 2018. He was born in La Crosse, Wisconsin, and earned a bachelor’s in chemistry at the University of Wisconsin in La Crosse. Next, he earned a doctorate from Iowa State University and did postdoctoral work at the Mayo Clinic in Rochester, Minnesota. In 1989, he joined UNL as an assistant professor of chemistry and quickly rose through the ranks. He has won many awards and, for the past 13 years, has been the James Hewet University Professor of Chemistry. Allow me to share some remarkable facts about Dave before we get into …

Role Of Wadsley Defects And Cation Disorder To Enhance Monb12O33 Diffusion, Cj Sturgill, Manish Kumar, Nima Karimitari, Iva Millisavljevic, Coby S. Collins, Aaron Hegler, Hsin-Yun Joy Chao, Santosh Kiran Balijepalli, Scott T. Misture, Christopher Sutton, Morgan Stefik

Faculty Publications

Wadsley-Roth (WR) niobates have emerged as high-rate anode materials that can combine rapid ionic diffusion with good electronic conductivity. WR compounds have been defect-enhanced by limited annealing, however, such materials often contain multiple types of defects. In particular, both Wadsley defects (variable block size) and transition metal disorder have the potential to modify transport rates, however the corresponding effects are not well understood mechanistically. Here, MoNb12O33 (MNO) was calcined at two different temperatures to compare a defect-rich condition (MNO-800) with a proximal order-rich condition (MNO-900) as assessed through XRD, XANES, EXAFS, and STEM characterizations. Galvanostatically cycled lithium half cells of …

Remediation Of Ammonium Perrhenate Via Tris(2,2’-Bipyridine)Ruthenium(Ii) Chloride, Kaylin L. Thomas, Sandra A. Abdellah, Alvin A. Holder

Knowledge and Creativity Expo

Pertechnetate (TcO₄⁻) is a persistent radioactive byproduct resulting from the decay of uranium-235 or plutonium-239 in the nuclear fuel cycle. Its high environmental mobility, long half-life, and significant beta radiation make TcO₄⁻ a critical contaminant. Structurally tetrahedral and water-soluble, TcO₄⁻ behaves similarly to the sulfate anion, facilitating its rapid introduction into ecosystems.

It bioaccumulates in lower-level organisms, propagating radioactive and toxic effects through food chains. In mammals, technetium-99 accumulates in the thyroid and may also impact fetal development. Its small charge, chemical stability, and solubility present significant challenges for effective remediation.

Current remediation methods often suffer from poor selectivity, dependence …

Advancing Environmental Justice Through Chemical Education: Perspective From New Orleans’ Water And Air Quality Challenges, Ja’Lynn Keller, Sita Aggarwal, Rami A. Al-Horani, Morewell Gasseller, Navneet Goyal

Faculty and Staff Publications

New Orleans, Louisiana, faces profound environmental vulnerabilities arising from the convergence of industrial pollution, urban runoff, and climate change–driven weather events. This paper examines systemic challenges affecting water and air quality in the region, with particular focus on low-income and marginalized communities disproportionately burdened by environmental degradation. Drawing on educational and community-based monitoring initiatives at Xavier University of Louisiana and Southeastern Louisiana University, we highlight the integration of student learning with real-time data collection of contaminants such as fecal coliforms, heavy metals, hydrocarbons, and polycyclic aromatic hydrocarbons (PAHs). The aftermath of Hurricane Katrina revealed significant fecal contamination in sediment layers, …

Analysis Of Novel Cannabis Products Labeled As Containing Thc-Jd, Kaelas R. Munger, Carlton C. B. Bone, Killian M. Anreise, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Objective:

THC-JD (tetrahydrocannabioctyl) is a semi-synthetic cannabinoid with an eight-carbon C3 side chain, present in only trace amounts in hemp, requiring synthesis for commercial use. It has been promoted as potentially 19 times more potent than delta-9-THC, consistent with enhanced CB1 receptor affinities for cannabinoids with 7-8 carbon C3 side chains. While one peer-reviewed report identified THC-JD (tetrahydrocannabioctyl) in Japanese online products, an anecdotal report from the U.S. suggests mislabeling. Method: To inform regulatory efforts and consumer awareness and to address these discrepancies, this study chemically analyzed five U.S. commercial cannabis vape products marketed as containing THC-JD. Results: Utilizing GC-MS …

Microstructural Evolution And Precipitate Control In Boron-Doped Ni-Mn-Ti Shape Memory Alloys Via Thermal Processing, Na Liu, Marcia Ahn, Subrata Ghosh, Dipika Mandal, Bed Poudel, Wenjie Li

Biochemistry, Chemistry & Physics: Faculty Publications

Elastocaloric cooling, which leverages stress-induced phase transformation in shape memory materials, represents a sustainable and energy-efficient alternative to conventional vapor-compression cooling systems. Central to optimizing these materials is understanding how thermal processing history dictates phase formation, microstructure, and thermal properties. In this study, we investigated the (Ni50Mn31.5Ti18)99.8B0.2 compound synthesized via vacuum induction melting and arc melting, followed by water quenching. Induction melting results in needle-like, boron-rich precipitates within the martensite lattice. In contrast, vacuum arc melting promoted precipitate growth at the grain boundaries. The vacuum arc melting sample exhibits ~82% martensite phase fraction, a near-ambient transformation temperature of ~277 K, …

Determination Of Trace Amounts Of Pb2+ And Cu2+ Ions In The Ohio River With Anodic Stripping Voltammetry And Flame Atomic Absorption Spectroscopy To Test Water Contamination From Factories., Eliana Purcell

The Cardinal Edge

In this project, water near factories in Rubbertown, Louisville, KY were tested to see if a significant enough amount of waste is deposited in the Ohio River that the concentrations of Pb2+ and Cu2+ exceed the maximum contaminant levels the World Health Organization (WHO) and the United States Environmental Protection Agency (EPA) have set in place. Waste from industrial factories may contain contaminants that have negative effects on aquatic ecosystems and even human health, so two potentially harmful metal ions were tested. The concentration of Cu2+ in water samples was detected through flame atomic absorption spectroscopy (FAAS), and the concentration …

The Dual-Specificity Phosphatase Jsp1 Regulates Neutrophil Adhesion Via Integrin-Src Signaling In Vascular Inflammation, Li Li

BCES: Faculty Publications

The c-JUN N-terminal kinase (JNK) signaling pathway plays an important role in regulating the innate immune response. Immune signaling is governed by the coordinated activity of protein kinases counter-balanced by protein phosphatases; however, the importance of the latter family of enzymes is less well understood. c-JUN N-terminal kinase (JNK)-stimulatory phosphatase 1 (JSP1, also known as DUSP22) has been implicated as a positive regulator of JNK signaling, yet its role in innate immunity is not clear. Using a mouse model of the local Shwartzman reaction, we show that JSP1 is essential for LPS-TNF-alpha-induced vascular injury. JSP1-knockout mice exhibited reduced vascular hemorrhage. …

Polyherbal Phytochemicals As Multi-Target Inhibitors Of Key Breast Cancer Proteins: A Computational Approach, Nadia Wahyuningsih, Nashi Widodo, Sri Rahayu, Muhaimin Rifa’I

Karbala International Journal of Modern Science

Breast cancer is a primary worldwide health concern, and conventional therapies often cause side effects. This study was performed to investigate the therapeutic potential of a polyherbal formulation containing Curcuma longa, Phyllanthus niruri, Ziziphus mauritiana, Nigella sativa, and Annona muricata as multi-target inhibitors against breast cancer protein targets using molecular docking and molecular dynamics in silico approach. Bioactive compounds were analyzed using Liquid Chromatography High-Resolution Mass Spectrometry (LC-HRMS) to identify the extract's phytochemicals. The compounds were examined for drug-likeness, membrane permeability, bioactivity, and toxicity. The inhibitory ability against the proto-oncogene pathway, which is commonly dysregulated and mutated in breast cancer, …

Synthesis And Characterization Of Ti-Enhanced F75/Ha Functionally Graded Materials Fabricated By Powder Metallurgy, Afrah M. Al Hussainey, Aseel Mustafa, Randa Kamel Hussain

Karbala International Journal of Modern Science

Functionally graded materials (FGMs) are a highly advanced class of biomaterials with graded structure and properties, enabling the fabrication of physiologically and mechanically compatible materials for use in various medical devices. This study aims to produce a functional-grade material based on a cobalt-chromium-molybdenum alloy (F75) reinforced with 4% titanium (Ti) and hydroxyapatite (HA). This will enhance the material's mechanical properties, corrosion resistance, and bioactivity, making it suitable for use as a bone substitute. The natural eggshells were washed, burnt, and chemically processed to form hydroxyapatite with a Ca/P proportion of 1.67. FTIR showed that phosphate and OH groups were separate, …

Extension Of The Local Vibrational Mode Theory To Periodic Systems, Filippo Bodo

Chemistry Theses and Dissertations

Over the years, vibrational spectroscopy was used to gain a deeper understanding of the electronic structure and the chemical bond in both molecular and periodic systems. In this framework, the Local Vibrational Mode Theory (LVMT), as first introduced by Konkoli and Cremer in 1998, provides a unique tool to quantify the strength of a chemical bond, and better interpret the molecular vibrational spectra, thanks to the adiabatic force constants ($k^a$) and the composition of normal modes (CNM). While LVMT was originally developed for molecular systems, its application to periodic solids has remained limited. This thesis presents a complete and systematic …

Peruvian Pinniped Teeth Trace Element Data-Tracking Ecosystem Variabilites Through Trace Element Record Found In Peruvian Pinniped Dentin, Dimitrios Giarikos, Amy Hirons, Ally E. Sheehan, Radleigh Santos

SECLER Data

The South American sea lion (Otaria byronia; SASL) and the Peruvian fur seal (Arctocephalus australis; PFS) are apex predators within the Humboldt Current ecosystem, where population dynamics respond to both natural variability and anthropogenic pressures, including El Niño–Southern Oscillation (ENSO) events and coastal mining. This study quantified 18 trace elements (TEs) in canine dentin from both species collected at Punta San Juan, Peru using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to evaluate long-term environmental exposure. Because dentin is deposited incrementally, it preserves a chronological chemical archive reflecting ontogenetic shifts in diet and habitat use. Overall, TE concentrations were broadly similar …