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Cloud Condensation Nuclei Activity Of Fresh And Aged Phenolic Acid Aerosol Particles, Emily A. Nortmann Jan 2025

Cloud Condensation Nuclei Activity Of Fresh And Aged Phenolic Acid Aerosol Particles, Emily A. Nortmann

Honors Undergraduate Theses

In recent years, the incidence of wildfires has considerably increased, with fire seasons starting earlier and ending later than usual due to changes in snowpack, precipitation, and temperature, which are attributed in part to climate change. Wildfires are responsible for the emission of a variety of gases and organic aerosol particles in the atmosphere with profound impacts on air quality, visibility, and human health. The aerosol particles produced by wildfires can contribute to climate change by scattering or absorbing solar radiation, affecting the radiative balance of the planet through cooling or warming effects, or by acting as cloud condensation nuclei …


Synthesis Of Novel Schiff Bases And Their Metal Complexes, Ryan J. Lukkarinen Jan 2025

Synthesis Of Novel Schiff Bases And Their Metal Complexes, Ryan J. Lukkarinen

Theses and Dissertations

Presented in this thesis is the synthesis and characterization of multiple thiosemicarbazones and dithiocarbazates, as well as their corresponding metal complexes. Chapter 1 is an introductory chapter exploring the significance and potential applications of this work. Chapter 2 focuses on thiosemicarbazone synthesis and characterization. Chapter 3 describes the synthesis and characterization of dithiocarbazates. Chapter 4 details metal complex synthesis using the previously described ligands. Chapter 5 summarizes the conclusions of the research and future work that may stem from it.


High Throughput, Solid Sample Analysis With Cone-Based Mass Spectrometric Ionization Sources, Emily J. Wiggins Jan 2025

High Throughput, Solid Sample Analysis With Cone-Based Mass Spectrometric Ionization Sources, Emily J. Wiggins

Theses and Dissertations

The widespread presence of environmental and consumer-product contaminants (e.g. trace metals, opium alkaloids) has underscored the need for rapid, reliable, and high-throughput analytical techniques that are capable of handling complex solid samples. While traditional mass spectrometric (MS) methods tend to have high sensitivity and accuracy, they often require labor-intensive and time-consuming sample preparation steps that limit throughput and field applicability. This thesis investigates the use of 3D-Printed Cone Spray Ionization-Mass Spectrometry (3D-PCSI-MS) as an ambient ionization technique for the direct screening of contaminants from solid matrices, eliminating the need for traditional sample preparation and allowing for real-time analysis.

In …


Cfd Analysis Of Hydrodynamic Cavitation Through An Orifice: Influence Of Different Inlet Pressures And Number Of Orifice Holes, Lemthong Chanphavong, Vongsavanh Chanthaboune, Keophousone Phonhalath Jan 2025

Cfd Analysis Of Hydrodynamic Cavitation Through An Orifice: Influence Of Different Inlet Pressures And Number Of Orifice Holes, Lemthong Chanphavong, Vongsavanh Chanthaboune, Keophousone Phonhalath

ASEAN Journal on Science and Technology for Development

Hydrodynamic cavitation (HC) is considered an energy-efficient process with high potential for utilization in many chemical processes. This study presents a computational fluid dynamics (CFD) analysis of cavitating flow through an orifice with a constant flow area. The Reynolds-Averaged Navier-Stokes (RANS) equations, coupled with turbulence and cavitation models, are employed to capture the complex flow behaviors. The effects of inlet pressures and number of orifice-holes on cavitation behavior are investigated. Result of the numerical simulation is validated with the existing experimental data from the literature. The CFD study revealed that cavitation initiates just behind the inlet edge of the orifice …


Biomechanics Of The Atherosclerotic Lipidome: (Un)Expected Statin Interactions And Membrane Remodelling, Ethan M. Fong Jan 2025

Biomechanics Of The Atherosclerotic Lipidome: (Un)Expected Statin Interactions And Membrane Remodelling, Ethan M. Fong

Pomona Senior Theses

Statins interact with lipid membranes in ways that shape their pharmacokinetics, off-target effects, and pleiotropic actions, yet these interactions' mechanical and biophysical consequences remain poorly understood. This thesis employs a combination of surface plasmon resonance (SPR), quartz crystal microbalance with dissipation monitoring (QCM-D), and rheological modelling to characterize how representative statins intercalate within biomimetic supported lipid bilayers (SLBs) of healthy and diseased composition. SPR reveals that lipophilic statins exhibit higher apparent affinities and slower dissociation kinetics, especially in cholesterol- and anionic lipid-rich membranes. QCM-D analyses demonstrate that statins alter membrane mass, dissipation, and interfacial stiffness in a statin- and membrane-dependent …


Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts Jan 2025

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …


Explorations Of Dna-Single-Walled Carbon Nanotube Interactions To Develop Multiplexed Molecularly Specific Biosensors For Inflammation, Amelia K. Ryan Jan 2025

Explorations Of Dna-Single-Walled Carbon Nanotube Interactions To Develop Multiplexed Molecularly Specific Biosensors For Inflammation, Amelia K. Ryan

Dissertations and Theses

Inflammatory cytokines such as interleukin-6 (IL-6) and interleukin-12 (IL-12) are central regulators of immune signaling and key biomarkers of disease, yet existing assays for their detection remain slow, invasive, and lack multiplexing ability. This dissertation advances the development of single-walled carbon nanotube (SWCNT) optical nanosensors capable of real-time, multiplexed, and molecularly specific cytokine detection through innovative use of single-stranded DNA (ssDNA) interfaces.

First, an IL-6-specific DNA aptamer was employed as both a dispersing agent and recognition probe for SWCNT fluorescence sensing. Sequence modifications, including anchor domains, truncations, and thermally induced refolding, were systematically tested to optimize sensitivity and selectivity. The …


The Role Of Leptin In The Regulation Of The Soluble Amyloid Precursor Protein Alpha (Sappa) Levels In Non-Small Cell Lunch Cancer (Nsclc) Cell Media, Benjamin Haddad Jan 2025

The Role Of Leptin In The Regulation Of The Soluble Amyloid Precursor Protein Alpha (Sappa) Levels In Non-Small Cell Lunch Cancer (Nsclc) Cell Media, Benjamin Haddad

Senior Honors Theses and Projects

We previously found that the levels of soluble amyloid precursor protein α (sAPPα) are partly regulated by acetylcholinesterase (AChE) in human non-small cell lung cancer cell lines A549 (p53 wild-type) and H1299 (p53-null). In this study, we hypothesize that sAPPα is partly regulated by leptin, a hormone classically recognized for its anorexigenic role in appetite regulation— yet recently shown to play a role in cancer cell signaling. It was observed that cells treated with leptin exhibited greater concentrations of sAPPα and lower concentrations of Aβ40/42 in the media compared to those of cells left untreated. An opposite effect was observed …


Development, Synthesis And Characterization Of Advanced Low- Cobalt And High-Nickel Cathode Materials For Lithium-Ion Batteries, Arjun Patel Jan 2025

Development, Synthesis And Characterization Of Advanced Low- Cobalt And High-Nickel Cathode Materials For Lithium-Ion Batteries, Arjun Patel

Theses and Dissertations

This dissertation focuses on the improvement of structural and electrochemical stability of active materials for lithium-ion batteries. It explores the modification strategies to mitigate the issues related to Ni-rich cathode materials, along with the continuous production of cathode precursors using a slug flow reactor to improve the quality of the product.

The First part of the dissertation examines the effect of substitution of cobalt with aluminum and iron on the electrochemical stability of Ni-rich lithium nickel cobalt manganese oxide (NCM) materials. This study investigates how Al and Fe doping work and how they impact the performance and stability of these …


Facile Synthesis Of Gold, Copper, And Silicon Nanostructures By Laser Ablation In Liquid, Nicholas Simpson Jan 2025

Facile Synthesis Of Gold, Copper, And Silicon Nanostructures By Laser Ablation In Liquid, Nicholas Simpson

Theses and Dissertations

Metal nanoparticle (NP) synthesis is a continually evolving area of research, owing to the widespread application of NPs in fields such as catalysis, drug delivery, and biosensing. Compared to bulk metal material, NPs contain a larger proportion of surface atoms and exhibit unique optical properties, thus making them ideal for applications where maximizing surface interactions is key. Moreover, their compositions can be altered in several different ways, as evidenced by metal alloy, core/shell, supported, and defective NPs. While conventional synthesis methods are capable of producing NPs in large quantities, they often require conditions of high temperature and pressure, strong reducing …


Chromatographic And Electrophoretic Analysis Of Lignin-Derived Monomers And Dimers: Extraction Method Development And Evaluation Of Cyclodextrins For Recovery, Anjam Sadik Jan 2025

Chromatographic And Electrophoretic Analysis Of Lignin-Derived Monomers And Dimers: Extraction Method Development And Evaluation Of Cyclodextrins For Recovery, Anjam Sadik

Theses and Dissertations--Chemistry

Biorefineries play a vital role in reducing dependence on fossil fuels and addressing global warming concerns. Unfortunately, investment in biorefineries remains limited due to economic sustainability concerns. One approach to enhance the economic viability of biorefineries is by fully utilizing the potential of feedstocks, particularly lignocellulosic biomass, which is commonly used in these processes. Traditional processing methods often alter the lignin portion of biomass, making it unsuitable for further utilization. However, when retained in its native form, lignin can serve as a valuable source of chemicals that contribute to the economic sustainability of biorefineries.

The lignin-first approach, which removes lignin …


Catalytic Deoxygenation Of Oleaginous Biomass To Renewable Diesel And Sustainable Aviation Fuel Via Decarboxylation/Decarbonylation, Chukwudalu Great Umenweke Jan 2025

Catalytic Deoxygenation Of Oleaginous Biomass To Renewable Diesel And Sustainable Aviation Fuel Via Decarboxylation/Decarbonylation, Chukwudalu Great Umenweke

Theses and Dissertations--Chemistry

Several technologies have been developed to produce hydrocarbon biofuels – renewable diesel (RD) and sustainable aviation fuel (SAF) – from fats, oils, and greases (FOG), with the hydroprocessing of esters and fatty acids (HEFA) representing one of the most mature pathways. In its current form, HEFA is mainly reliant on the hydrodeoxygenation (HDO) reaction, which has several drawbacks since HDO requires large amounts and pressures of hydrogen, feedstocks of high purity and cost, as well as problematic sulfided catalysts that risk contaminating the biofuel product with sulfur. A process based on decarboxylation/decarbonylation (deCOx) offers an attractive alternative to …


Insights Into Factors Influencing Radical Coupling Chemistry Of Monolignols During Lignification And Induced Changes In Plant Secondary Metabolism, Rachel Poornima Sutherland Jan 2025

Insights Into Factors Influencing Radical Coupling Chemistry Of Monolignols During Lignification And Induced Changes In Plant Secondary Metabolism, Rachel Poornima Sutherland

Theses and Dissertations--Chemistry

Lignin is a complex aromatic biopolymer and an important constituent in plant cell walls. The process of lignin biosynthesis, known as lignification, is poorly understood and challenging to study but has important implications in a variety of fields including sustainable energy, bioengineering, and materials science and is therefore of interest to pursue. In the final stage of lignification, H-, G-, and S-monolignols are oxidized by laccase and peroxidase enzymes to generate radical species that couple to form dimers and further oligomeric species to ultimately produce the lignin polymer. Biomimetic lignin model systems utilize in vitro oxidative coupling reactions as an …


Redox Control In A Fused Electron Transfer Flavoprotein From A Thermophilic Archaeon And Expanded Significance Of A Hydrogen Bond From A Conserved Histidine Residue That Contributes To Flavin Redox Tuning And Activation For Covalent Modification, Debarati Das Jan 2025

Redox Control In A Fused Electron Transfer Flavoprotein From A Thermophilic Archaeon And Expanded Significance Of A Hydrogen Bond From A Conserved Histidine Residue That Contributes To Flavin Redox Tuning And Activation For Covalent Modification, Debarati Das

Theses and Dissertations--Chemistry

In absence of O2 as terminal electron acceptors in anaerobic bacteria and archaea, carbohydrate metabolism is 15 times less efficient compared to aerobic energy metabolism resulting in energy deficit conditions. Despite their meager resources these anaerobes were able to generate H2 and a chemiosmotic potential able to drive energy demanding reactions such as CO2 or N2 fixation. These observations raised concerns as production of high energy reductants (H2) from mediocre fuels (NADH) defied the laws of thermodynamics.

In 2008, a known mechanism “electron bifurcation” but with flavins as redox mediators instead of quinones was …


Towards Automating The Study And Discovery Of Electroactive Π-Conjugated Molecules, Rebekah Ann Duke-Crockett Jan 2025

Towards Automating The Study And Discovery Of Electroactive Π-Conjugated Molecules, Rebekah Ann Duke-Crockett

Theses and Dissertations--Chemistry

Chemistry is entering a new paradigm of automation and data-driven discovery. Automated discovery is grounded in well-curated “big data.” As generative and predictive models fueled by simulation data see growing success, emerging robotic automation enables the generation of unprecedented volumes of experimental data. Automation-powered, data-driven approaches hold tremendous potential for groundbreaking insights and innovations, particularly in the study and discovery of electroactive π-conjugated molecules. Realizing this potential, however, requires democratizing chemical data and the automation needed to generate and use it. There is a need to expand access to the tools for findable, accessible, interoperable, and reusable (FAIR) data management …


Design And Synthesis Of Novel Ligands For Bioorthogonal Catalysis, Asymmetric Synthesis, And Ferromagnetic Behavior, Alexander G. Olivelli Jan 2025

Design And Synthesis Of Novel Ligands For Bioorthogonal Catalysis, Asymmetric Synthesis, And Ferromagnetic Behavior, Alexander G. Olivelli

Theses and Dissertations--Chemistry

Small molecule metal complexes have diverse applications including usage as catalysts, single molecule magnets, photosensitizers and pharmaceuticals. The first research project in this work reports a new ligand which dimerizes upon coordination to afford a trinuclear Cu(I) complex. Due to the coordination geometry of the Cu(I) metal centers, paired with the strong nitrogen coordinating groups, the resulting complex is resistant to oxidation even in the presence of strong oxidants. The complex is shown to be efficient in the CuAAC reaction and used to tag anticancer drug candidates in vitro. The next project focuses on a series of amidine-based ligands featuring …


Machine Learning Models For Molecular-Based Functional Organic Materials, Moses Ogbaje Jan 2025

Machine Learning Models For Molecular-Based Functional Organic Materials, Moses Ogbaje

Theses and Dissertations--Chemistry

Organic semiconductors (OSC) are of interest for a wide range of flexible optoelectronics applications, including transistors, solar cells, and sensors, to name a few. Despite their promise, the design and optimization of OSC pose significant challenges due to the complexity of the structures of the molecular building blocks, varied packing configurations of these building blocks in the solid state, which impacts the optical and electronic response, and sensitivity of the solid-state packing to material processing conditions. Accurately predicting the solid-state properties of OSC traditionally requires high-level quantum mechanical methods. These methods, however, can be computationally demanding, particularly for large molecules …


Investigation Of D-Π-A Re (1) Complexes For The Homogenous Photocatalytic Reduction Of Co2, Ryan M. Chafin Jan 2025

Investigation Of D-Π-A Re (1) Complexes For The Homogenous Photocatalytic Reduction Of Co2, Ryan M. Chafin

Theses and Dissertations--Chemistry

Increasing anthropogenic emission of CO2 into the atmosphere is a global issue that shows no signs of deceleration due to the current trends in dependencies on fossil fuels for energy demand. Although deleterious in nature, this greenhouse gas can serve as a useful feed-stock for the production of small-carbon-chain commercial chemicals if the factors owing to its inertness can be overcome. Fortuitously, CO2’s chemically inert nature is already circumvented in nature through an elegant cascade of biochemical reactions known as photosynthesis, which nearly all plants and some families of bacteria exploit to produce simple sugars for metabolic …


Targeted Mitigation Strategies To Reduce Secondary Emissions In Co2 Capture Systems, Keemia Abad Jan 2025

Targeted Mitigation Strategies To Reduce Secondary Emissions In Co2 Capture Systems, Keemia Abad

Theses and Dissertations--Chemistry

Global CO2 emissions from industrial, power generation and transportation sources has led to the call for increased implementation of carbon capture strategies. The most developed of these is point source carbon capture, which refers to the process of capturing CO2 directly from large (point) source emitters, before the CO₂ is released into the atmosphere. The challenge becomes separating CO2 from the other components of the emitted gas, mainly nitrogen. These CO2 capture processes typically involve the use of aqueous solutions of amines to absorb (capture) CO₂ from the gas stream, where the CO2 and the …


Exploring The Relationships Between Molecular Structure And Crystal Packing In Small-Molecule Organic Semiconductor Materials, Dean A. Windemuller Jan 2025

Exploring The Relationships Between Molecular Structure And Crystal Packing In Small-Molecule Organic Semiconductor Materials, Dean A. Windemuller

Theses and Dissertations--Chemistry

Organic semiconductor materials (OSCs) are rapidly becoming a vital part of the technological landscape. They possess unique properties that make them attractive for the electronics industry. Relatively low-temperature and low-cost processing are a large part of the promise of OSCs. Perhaps more importantly, organic materials can be modified in a relatively straightforward manner, presenting an opportunity for them to be tuned and adapted to a variety of purposes and applications. Polycyclic aromatic hydrocarbons (PAHs) form a large group within the field of OSC research. Some of the most promising high-performance materials in this category to-date are acenes and heteroacenes. This …


Effects Of A-Site Cation Structure And B-Site Metal On Optical And Electronic Properties Of 2d Ruddlesden-Popper Phase Tin-Based Hybrid Perovskites, Henry Pruett Jan 2025

Effects Of A-Site Cation Structure And B-Site Metal On Optical And Electronic Properties Of 2d Ruddlesden-Popper Phase Tin-Based Hybrid Perovskites, Henry Pruett

Theses and Dissertations--Chemistry

Organic metal halide perovskites (HPs) are attractive materials for a variety of electronic applications due to their low cost, tunable band gaps, excellent charge transport properties, and high photoluminescence efficiency. As such, HPs are being investigated for use in solar cells, photodetectors, X-ray detectors, light emitting diodes, field effect transistors, lasers, resistive random-access memory, etc. Currently the most popular metal used in HPs is lead, but the use of lead comes with the potential for heavy metal exposure. Tin-based perovskites offer a less hazardous alternative, but their optoelectronic properties lag behind those of lead and less work has been done …


Design, Synthesis, And Evaluation Of Di-Peptide Probes For Stoichiometric Quantitative Analysis Of Antibodies, Taylor Gladson Jan 2025

Design, Synthesis, And Evaluation Of Di-Peptide Probes For Stoichiometric Quantitative Analysis Of Antibodies, Taylor Gladson

Graduate Research Theses & Dissertations

Quantitative information on biomarkers is a decisive factor in a wide range of situations concerning individual and public well-being. Under certain circumstances, the availability of accurate quantitative information can even become a matter of life or death. Therefore, the ability to make quantitative measurements in point-of-care (POC), do-it-yourself (DIY), and limited resource settings (LRS) is crucial for diagnostics, disease management, food safety, biomedical research, forensics, and other areas.In the work, we develop a POC/DIY/LRS-compatible platform for unambiguous (yes/no type) quantitative analysis of antibodies. The heart of the approach is negative cooperativity-based target – probe binding. The binding modality yields a …


Point Of Care (Poc) - Compatible Detection Platform Based On Catalase Activity Of Dna G-Quadruplexes, Elzbieta Iwaniuk Jan 2025

Point Of Care (Poc) - Compatible Detection Platform Based On Catalase Activity Of Dna G-Quadruplexes, Elzbieta Iwaniuk

Graduate Research Theses & Dissertations

The goal of our project is to develop an equipment-free signal readout platform suitable for potential molecular diagnostics applications. In the development, we adhere to (RE)ASSURED (Real time, Ease of specimen collection, Affordable, Sensitive, Specific, User-Friendly, Robust, and rapid, Equipment free, Deliverable) criteria. As a proof of concept, we focus on oligonucleotide targets. Our detection system incorporates an activatable catalytic complex that causes the decomposition of Hydrogen Peroxide (H2O2); oxygen (O2) bubbles released in reaction serve as signal readout. The catalytic system comprises of DNA G-quadruplex and Hemin. The catalytic activity and, therefore, the signal are triggered in the presence …


Gas–Phase Studies Of C–H Activation And Dehydrogenation Of Liquid Organic Hydrogen Carrier Model Compounds, Robert S. King Jan 2025

Gas–Phase Studies Of C–H Activation And Dehydrogenation Of Liquid Organic Hydrogen Carrier Model Compounds, Robert S. King

Graduate Research Theses & Dissertations

In the transport of hydrogen, cryogenic methods are often utilized; however, this method is high in energy cost and not sufficiently safe in terms of release prevention. Liquid organic hydrogen carriers (LOHCs) are one of the many methods being developed for a robust and safe hydrogen energy infrastructure. One aspect of LOHCs with a rich research field as of late is dehydrogenation techniques to liberate stored hydrogen gas for energy consumption. This process currently requires excessive cost (environmental and monetary), specialty catalysts using expensive metals like palladium for the selective dehydrogenation without coking of the catalyst surface. In search for …


Synthesis And Design Of Clpp Activators As Novel Antibiotics, Schyler Odum Jan 2025

Synthesis And Design Of Clpp Activators As Novel Antibiotics, Schyler Odum

Theses and Dissertations (ETD)

Purpose. Design and synthesize novel compounds to treat Staphylococcus aureus infections by targeting the dysregulation of the Casein Protease P, ClpP. Methods. Utilize established chemical methods to synthesize ureadepsipeptides, small-molecule ClpP activators, and ureadepsipeptide hybrids. Assess their effectiveness by using minimum inhibitory concentration assays and in vitro biochemical assays for ClpP activation. Explore their potential as antibiotics through mitochondrial toxicity tests, glucose/galactose assays, and biophysical measurements related to metabolism and clearance, including thermal shift and surface plasmon resonance assays. Results. Synthesized and tested 33 novel compounds, comprising a total of 80 synthetic steps. Conclusion. The three-part conclusion from the dissertation …


Analysis Of Gas Station Drugs Using Gas Chromatography Mass Spectrometry And Fourier Transform Infrared Spectroscopy, Megan Joos Jan 2025

Analysis Of Gas Station Drugs Using Gas Chromatography Mass Spectrometry And Fourier Transform Infrared Spectroscopy, Megan Joos

All ETDs from UAB

Gas stations and head shops are a seemingly safe and legal marketplace for drug purchase. However, although marketed as dietary supplements or cognitive enhancers, the products sold there have been known to contain psychoactive substances which may be mislabeled or actually contain regulated substances. This study investigates the composition of such products, specifically those labeled as kratom and non-kratom Mitragyna species using gas chromatography-mass spectrometry (GC-MS) and those labeled as phenibut using GC-MS and fourier transform infrared spectroscopy (FTIR). Samples were acquired from retailers in the Birmingham, AL area. The products underwent both qualitative and quantitative analysis of their ingredients …


Cui-Derived Cuxo Thin Films Development Via Thermal Oxidation For Lead-Free Perovskite Solar Cells, Md Jakir Hossen, Md Shahinuzzaman, M. S. Jamal, Suhana Mohd Said, S. F.W.M. Hatta, Md Helal Miah, Mayeen Uddin Khandaker, Mohammad Nur-E-Alam, Mohammad Aminul Islam Jan 2025

Cui-Derived Cuxo Thin Films Development Via Thermal Oxidation For Lead-Free Perovskite Solar Cells, Md Jakir Hossen, Md Shahinuzzaman, M. S. Jamal, Suhana Mohd Said, S. F.W.M. Hatta, Md Helal Miah, Mayeen Uddin Khandaker, Mohammad Nur-E-Alam, Mohammad Aminul Islam

Research outputs 2022 to 2026

The development of low-cost, stable, and efficient hole transport layers (HTLs) is crucial to the advancement of lead-free perovskite solar cells. In this work, a solution-based oxidation process is employed to convert spin-coated copper iodide (CuI) films into mixed-phase copper oxide (CuxO) thin films comprising Cu₂O and CuO. Oxidation occurs under moderate temperatures (200–300°C), leading to uniform, compact, and highly conductive p-type films with tunable bandgaps. Structural, morphological, and optical analysis confirms successful phase transformation, and measurements of Hall effect reveal maximum mobility of holes of 26.7 cm2 V−1 s−1 for double-coated films annealed at 300°C. Device …


Lead-Free Alternatives And Toxicity Mitigation Strategies For Sustainable Perovskite Solar Cells: A Critical Review, Md Helal Miah, Mayeen Uddin Khandaker, Md Jakir Hossen, None Noor-E-Ashrafi, Ismat Jahan, Md Shahinuzzaman, Mohammad Nur-E-Alam, Mohamed Y. Hanfi, Md Habib Ullah, Mohammad Aminul Islam Jan 2025

Lead-Free Alternatives And Toxicity Mitigation Strategies For Sustainable Perovskite Solar Cells: A Critical Review, Md Helal Miah, Mayeen Uddin Khandaker, Md Jakir Hossen, None Noor-E-Ashrafi, Ismat Jahan, Md Shahinuzzaman, Mohammad Nur-E-Alam, Mohamed Y. Hanfi, Md Habib Ullah, Mohammad Aminul Islam

Research outputs 2022 to 2026

The growing global energy demand has prompted an increase in research into renewable energy conversion technologies. Although lead-based perovskite solar cells (PSCs) offer high efficiency as well as low manufacturing costs, the toxicity of the material is still a serious hurdle to their commercialization and widespread adoption. Amid ongoing efforts to develop lead-free perovskites, over the last few years, growing attention on mitigating the toxicity of lead by inhibiting the leakage of lead from PSCs has been observed. This review discusses the potential replacement of lead from PSCs and explores various approaches to mitigate lead leakage from PSCs. In addition, …


A Biogeochemical Perspective On Acidification And Buffering Capacity In The Piscataqua Estuary, Sanjana Varanasi Jan 2025

A Biogeochemical Perspective On Acidification And Buffering Capacity In The Piscataqua Estuary, Sanjana Varanasi

Master's Theses and Capstones

Coastal acidification is influenced not only by rising atmospheric CO2 and river-ocean mixing, but also by metabolic processes that alter seawater carbonate chemistry and buffering capacity. This study examines how sedimentary biogeochemical processes contribute to carbonate system variability in the Piscataqua Estuary, a tidally dynamic channel connecting Great Bay to the Gulf of Maine. The biogeochemical processes considered include sedimentary aerobic respiration, denitrification, sulfate reduction, and carbonate dissolution or precipitation. Two incubation experiments were conducted in September and October of 2024 at the University of New Hampshire’s Coastal Marine Laboratory (CML) to quantify changes in pH, dissolved inorganic carbon (DIC), …


Separation And Surface Examination Of Spacecraft Cabin Particulates, Grace A. Belancik Jan 2025

Separation And Surface Examination Of Spacecraft Cabin Particulates, Grace A. Belancik

Master's Theses

Particulate matter in the atmosphere is a known detriment to human health, but several factors affect any particulate’s particular toxicity including particle size, surface area, and chemical composition. Extensive studies have been conducted to examine particulate hazards on Earth, but in crewed spacecraft, like the International Space Station (ISS), the particulate environment is wholly unique due to both the controlled environment and lack of gravity. Atmospheric sampling studies are underway, but another convenient source of airborne particulates for analysis is the contents of the vacuum bags used by the astronauts to clean the air vents. However, no method currently exists …