Chemistry Commons^™

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

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 …

Adding 3,4-Methylenedioxy-Α-Cyclohexylaminopropiophenone To A Standard Operating Procedure (Sop) For Identifying Synthetic Cathinones Using Gas Chromatography-Mass Spectrometry, Napassawon Timpratoom

ETDs from 2020-2029

Synthetic cathinones were identified as new psychoactive substances (NPS) in the early warning advisory system by the United Nations Office on Drugs and Crime (UNODC). Synthetic cathinones have been commonly referred to as bath salts, which offered “legal highs” because they were not explicitly scheduled. These compounds were detected dur-ing the screening process in casework and required internal validation for confirmation. 3,4-methylenedioxy-α-cyclohexylaminopropiophenone was the target analyte for this study. It was alternatively named N-cyclohexyl methylone and “cyputylone." The aim of the study was to validate 3,4-methylenedioxy-α-cyclohexylaminopropiophenone into a Standard Operating Procedure (SOP) for identifying synthetic cathinones using gas chromatography/mass spectrometry …

Detection Of C60 Combination Bands In The Near-Ir Spectrum Of Tc 1, Morgan M. Giese, Vincent J. Esposito, Simon Van Schuylenbergh, Jan Cami, Els Peeters, Charmi Bhatt, Dries Van De Putte, A. G. G. M. Tielens, Michael J. Barlow, Jeronimo Bernard-Salas, Alessandra Candian, Bryan Changala, Nick L. J. Cox, Harriet L. Dinerstein, D. A. García-Hernández, Marco A. Gómez-Muñoz, Kay Justtanont, Kathleen E. Kraemer, Eric Lagadec, Arturo Manchado, Ana Monreal Ibero, Raghvendra Sahai, Ameek Sidhu, G. C. Sloan, N. C. Sterling, Jeremy R. Walsh, Roger Wesson, Joshua Cole Whitman, Albert Zijlstra

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We report the detection of a set of new near-infrared emission features between 3.5 and 5.2 μm in JWST/NIRSpec observations of Tc 1, the planetary nebula known for displaying the cleanest and most prominent mid-infrared cosmic fullerene spectrum. These broad features share the same spatial distribution as the well-known C₆₀ and C₇₀ mid-infrared emission bands, peaking in an asymmetric ring approximately 5″–6″ from the central star. Through comparison with new anharmonic quantum chemical calculations, we demonstrate that these features arise from C₆₀ combination bands, marking their first detection in an astrophysical environment. The total energy radiated …

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 …

Tuning Ion Mobility And Molecular Confinement In High-Performance Polymer Electrolytes For Energy Storage, Ezzeldien Yousef Muhammed Yousef

Theses and Dissertations

This research addresses the critical energy density limitations of aqueous supercapacitors, which are traditionally constrained by the narrow electrochemical stability window (ESW) of water 1.23 V. By employing two distinct molecular engineering strategies, this study developed high-performance electrolyte systems that significantly extend voltage stability and thermal resilience.

The first system, CsBr@PAM/HA, utilizes a polyacrylamide and hyaluronic acid hydrogel matrix. This system exploits the chaotropic nature of Cs⁺ ions to disrupt the aqueous hydrogen-bonding network, enhancing ionic conductivity to 104 mS cm^-1. Through systematic salt screening, CsBr was identified as the optimal electrolyte, enabling a stable 2.0 V …

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

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 …

Employing Ac And Dc Electrolysis To Modulate Electroenzymatic Pathways For Efficient And Stereoselective H-D Exchange, Wassim El Housseini, Rokas Gerulskis, Nibedita Behera, Huaijun Guan, Rohit G. Jadhav, Zachary A. Nguyen, Egor Baiarashov, Michael A. Pence, Vamshi Krishna Kamaja, Trevor Larkin, Long Luo, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Stereoselective hydrogen isotope exchange (HIE) at chiral centers is an increasingly important strategy for preparing labeled molecules, yet its practical implementation depends on reliable control of nicotinamide cofactor regeneration. Here we introduce a redox-programmable electroenzymatic platform for stereoselective HIE based on electrode-controlled manipulation of the nicotinamide cofactor state. A wired ferredoxin–NADP⁺ reductase (FNR) electrode enables reversible electrochemical interconversion of NADP⁺ and its deuterated reduced form (NADPD) directly from D2O. Coupling this cofactor cycling with enantioselective alcohol dehydrogenases (ADHs) establishes a reversible alcohol–ketone redox manifold that drives efficient and stereoselective H-D exchange at chiral alcohols. Stereochemical outcomes are programmed …

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

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

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

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 …

Investigation Of Portland Limestone Cement Blended With Biochar From Downdraft Gasification: Hydration Kinetics, Microstructure, Rheology, And Performance Mechanisms, Ugochukwu Ewuzie, Paul C. Ani, Abdulkareem O. Yusuf, Joseph D. Smith, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

The widespread adoption of Portland Limestone Cement (PLC) in U.S. concrete production has necessitated research into commercially available supplementary cementitious materials (SCMs) for formulating high-performance, low-carbon blended binders with PLC. This study investigated the influence of biochar (BC) in biochar-PLC composites (CBCs), focusing on hydration kinetics, microstructure, rheology, pore-solution chemistry, compressive strength, and the underlying mechanisms. Biochar was produced via downdraft gasification at 850 °C and incorporated into PLC at 5, 7, and 10% substitution by mass. Isothermal calorimetry and hydration data modeled using the Knudsen equation revealed that BC retarded early hydration but improved hydration degree and later-age heat …

Interview With Orca Winner Xiao Cheng Zeng; Unl Chemistry; Computational/Theoretical; Nebraska Ice & Gold Nanocages, Mark Griep, Xiao Cheng Zeng

UNL ORCA Interview Series

Xiao Cheng Zeng became a chemistry professor at the University of Nebraska-Lincoln in 1993, quickly rose through the ranks, and was in the department for 29 years. In 2022, he left to become head of the Department of Materials Science and Engineering at the City University of Hong Kong. Xiao was born in Beijing and earned a bachelor’s in physics at the University of Beijing in 1984. Next, he traveled 6800 miles east to Ohio State University in Columbus where he earned his doctorate in condensed matter physics. He followed that up with two postdoctoral experiences, first at the University …

Structure-Property Relationship In Low-Dimensional Cesium Metal Halides: Coordination Chemistry, Luminescent Mechanism And Optoelectronics Applications, Sheikh Jobe

Thesis/ Dissertation Defenses

Low-dimensional metal halides are gaining popularity in optoelectronic applications owing to their interesting optical properties and structural diversity. In general, low-dimensional metal halides refer to one-dimensional and zero-dimensional structures. The main difference between the two is that one-dimensional structures have chain-like connectivity, whereas zero-dimensional structures consist of isolated units. Their optical properties are mainly determined by the B-site metal ion, which is coordinated to halide ions in trigonal, tetrahedral, or octahedral geometry. In particular, copper (I) and manganese (II) metal halides are emerging as novel materials for solid-state lighting, and anti-counterfeiting applications. The two well-known phases of cesium copper (I) …

Emerging Catalysts And System Designs For High-Current-Density Co2 Electroreduction To Multicarbon Fuels And Chemicals Toward Industrial-Scale Applications, Godwin Uche Edor

Masters Theses

Electrochemical CO2 reduction (eCO2RR) offers a sustainable route to convert CO2 into value-added fuels and chemicals, particularly multicarbon (C2+) products due to their higher energy density and economic value compared to C1 counterparts. Industrial adoption of eCO2RR technology is hindered by the difficulty in stably reaching superior Faradaic efficiency (FE) for C2+ products at ≥ 200 mA cm-2 at low applied overpotential due to sluggish C–C coupling kinetics, competing reactions, and catalyst instability. Hence, we examine the recent advances in eCO2RR catalyst engineering strategies, such as nanostructural and electronic modifications of Cu-based catalysts (e.g., interfacial, surface, facet, and defect engineering, …

Regioselective Tellurination Reactions And Their Utilities, Itunu Comfort Olanrewaju

Masters Theses

This thesis provides a comprehensive study of regioselective tellurination and its applications by integrating experimental and computational techniques, with an aim of synthesizing libraries of organotellurium heterocycles. This study addresses existing challenges in regioselective tellurination, such as unpredictable regioselectivity and avoidance of toxic reagents by harnessing intramolecular Te…O coordination and electrophilic aromatic tellurination. This strategy enables the development of previously poorly accessible compounds including benzotellurazinones, 2-acylaminobenzotellurazoles, and previously unknown 2,3-dihydrobenzo [b] oxatelluranes, which were prepared by antiMarkovnikov anti-addition of TeCl4 to C-C triple bonds. Experimental studies were complemented by computational DFT analyses to provide mechanistic and energetic insight into the …

Biomedical Applications Of Structurally Defined Natural And Semi-Synthetic Saponins, Chaeeun Lim-Paik

ETDs from 2020-2029

Triterpenoid saponins are amphiphilic glycosides that exhibit a wide range of biological and pharmacological properties, including antifungal, antiviral, molluscicidal, hypoglycemic, and hypocholesterolemic effects. These biological and pharmacological properties make saponins attractive for diverse applications. In this work, we demonstrate three biological applications: (i) immunostimulant vaccine adjuvant, (ii) protein delivery enhancement, and (iii) gene transfection enhancement. In light of the strong structure dependence of saponin activity, expanding the structural diversity of available scaffolds is essential for establishing structure-activity relationships (SAR) across these applications. Here, we expanded our saponin collection through semi-synthetic derivatization and the isolation of new saponins from distinct natural …

Evaluation Of Solar Reflective Pigments For Use In Direct-To-Metal Coatings, William J. Diment

Master's Theses

Solar reflective coatings offer a promising strategy to mitigate the urban heat island effect by reducing absorption of near-infrared solar energy. This thesis project investigates the feasibility of incorporating near-infrared reflective pigments into waterborne direct-to-metal (DTM) latex coating systems while maintaining acceptable color comparison characteristics and coating performance. An all acrylic latex DTM formulation with titanium dioxide as the sole pigment was prepared and tinted with a variety of conventional and solar reflective commercial colorants across the yellow, red, blue, and green color ranges. Coatings were evaluated for solar reflectance, CIELAB color, gloss, contrast ratio, rheological behavior, accelerated ultraviolet weathering …