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Electrochemical-Method-Induced Strong Metal-Support Interaction In Pt-Cnt@Sno2 For Co-Tolerant Hydrogen Oxidation Reaction, Shen-Zhou Li, Zi-Jie Lin, Qi-An Chen, Zhao Cai, Qing Li Dec 2024

Electrochemical-Method-Induced Strong Metal-Support Interaction In Pt-Cnt@Sno2 For Co-Tolerant Hydrogen Oxidation Reaction, Shen-Zhou Li, Zi-Jie Lin, Qi-An Chen, Zhao Cai, Qing Li

Journal of Electrochemistry

Inducing the classic strong metal-support interaction (SMSI) is an effective approach to enhance the performance of supported metal catalysts by encapsulating the metal nanoparticles (NPs) with supports. Conventional thermal reduction method for inducing SMSI processes is often accompanied by undesirable structural evolution of metal NPs. In this study, a mild electrochemical method has been developed as a new approach to induce SMSI, using the cable structured core@shell CNT@SnO2 loaded Pt NPs as a proof of concept. The induced SnOx encapsulation layer on the surface of Pt NPs can protect Pt NPs from the poisoned of CO impurity in …


Dendrite-Free Strategies For Aqueous Zinc-Ion Batteries: Structure, Electrolyte, And Separator, Gang Wu, Wu-Hai Yang, Yang Yang, Hui-Jun Yang Dec 2024

Dendrite-Free Strategies For Aqueous Zinc-Ion Batteries: Structure, Electrolyte, And Separator, Gang Wu, Wu-Hai Yang, Yang Yang, Hui-Jun Yang

Journal of Electrochemistry

Continued growth in energy demand and increased environmental pollution constitute major challenges that need to be addressed urgently. The development and utilization of renewable, sustainable, and clean energy sources, such as wind and solar, are crucial. However, the instability of these intermittent energy sources makes the need for energy storage systems increasingly urgent. Aqueous zinc-ion batteries (AZIBs) have received widespread attention due to their unique advantages, such as high energy density, cost-effectiveness, environmental friendliness, and safety. However, AZIBs face significant challenges, mainly the formation of zinc dendrites that seriously affect the stability and lifetime of the batteries, leading to battery …


All-Solid-State Sodium-Ion Batteries: A Leading Contender In The Next-Generation Battery Race, Rui-Jie Zhu, Ze-Chen Li, Wei Zhang, Akira Nasu, Hiroaki Kobayashi, Masaki Matsui Dec 2024

All-Solid-State Sodium-Ion Batteries: A Leading Contender In The Next-Generation Battery Race, Rui-Jie Zhu, Ze-Chen Li, Wei Zhang, Akira Nasu, Hiroaki Kobayashi, Masaki Matsui

Journal of Electrochemistry

All-solid-state lithium-ion batteries (LIBs) using ceramic electrolytes are considered the ideal form of rechargeable batteries due to their high energy density and safety. However, in the pursuit of all-solid-state LIBs, the issue of lithium resource availability is selectively overlooked. Considering that the amount of lithium required for all-solid-state LIBs is not sustainable with current lithium resources, another system that also offers the dual advantages of high energy density and safety— all-solid-state sodium-ion batteries (SIBs) —holds significant sustainable advantages and is likely to be the strong contender in the competition for developing next-generation high-energy-density batteries. This article briefly introduces the research …


Contributions To Journal Of Electrochemistry, The Flagship Journal Of Chinese Chemical Society Electrochemical Committee, Will Be Listed As A New Recommendation Policy For China Youth Awards Of Electrochemist, Editorial Office Of J.Electrochem. Dec 2024

Contributions To Journal Of Electrochemistry, The Flagship Journal Of Chinese Chemical Society Electrochemical Committee, Will Be Listed As A New Recommendation Policy For China Youth Awards Of Electrochemist, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Optimization Of The Starch Chitosan-Based Flocculant Crosslinked By Ethylene Glycol Dimethacrylate On Removing Dypro 19 Textile Dye From Wastewater, Asep Nurohmat Majalis, Putri Ramadhani, Hendris Hendarsyah Kurniawan, Axel Dimaz Sanusi Pasaribu, Hafiizh Prasetia, Fitri Yuliani, Andreas Andreas, Hartati Hartati Dec 2024

Optimization Of The Starch Chitosan-Based Flocculant Crosslinked By Ethylene Glycol Dimethacrylate On Removing Dypro 19 Textile Dye From Wastewater, Asep Nurohmat Majalis, Putri Ramadhani, Hendris Hendarsyah Kurniawan, Axel Dimaz Sanusi Pasaribu, Hafiizh Prasetia, Fitri Yuliani, Andreas Andreas, Hartati Hartati

Karbala International Journal of Modern Science

Dyes used in industry, especially textile dyes, are one of the water pollutants that receive much attention because they are potentially toxic, carcinogenic, mutagenic, and generally challenging to decompose naturally. Textile dyes from wastewater can be removed through coagulation-flocculation. However, conventional coagulation-flocculation based on Fe and Al salts and synthetic polymers often leaves residual pollution. In this research, the performance of the new biopolymer-based flocculant, namely starch-ethylene glycol dimetacrylate-chitosan (SEC), which can act as coagulants and flocculants in solid-liquid separation of textile dyes, has been optimized using response surface methodology (RSM) approach. The influences of several independent variables, such …


Breast Cancer Area Identification In Mammograms Using Expectation Maximization Gaussian Mixture Model, Rizki Khoirun Nisa, Dian Kurniasari, Favorisen R. Lumbanraja, Warsono Warsono Dec 2024

Breast Cancer Area Identification In Mammograms Using Expectation Maximization Gaussian Mixture Model, Rizki Khoirun Nisa, Dian Kurniasari, Favorisen R. Lumbanraja, Warsono Warsono

Karbala International Journal of Modern Science

Breast cancer accounts for 25% of all cancer diagnoses and 16% of cancer-related deaths among women globally, with high mortality rates due to late diagnosis. Early detection relies on imaging techniques such as mammography, histopathology, and breast ultrasound, with mammography being the gold standard due to its proven to detect breast cancer, thus it is effective for breast cancer treatment. However, mammogram images often produce noise and artefacts, complicating early-stage cancer detection and emphasizing the need for advanced image processing. Clustering algorithms such as K-means and Expectation Maximization - Gaussian Mixture Model (EM-GMM) have shown potential in image segmentation. This …


Interactions Of The Sars-Cov-2 Viral Genome 3’-Untranslated Region With Viral And Host Rnas, Caleb Frye, Mihaela Rita Mihailescu Dec 2024

Interactions Of The Sars-Cov-2 Viral Genome 3’-Untranslated Region With Viral And Host Rnas, Caleb Frye, Mihaela Rita Mihailescu

Electronic Theses and Dissertations

This dissertation focuses on the characterization of RNA-RNA interactions within the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome and with host microRNAs. As the causative agent of coronavirus disease 2019 (COVID-19), SARS-CoV-2 has evolved rapidly since its appearance. This has warranted prompt characterization of the virus particularly of its single stranded RNA (ssRNA) genome. By using a combination of bioinformatics, biophysics, and/or biological assays, we analyzed the SARS-CoV-2 viral genomic RNA and uncovered interactions of genomic RNA with host RNAs, highlighting an underutilized method of targeting RNA viruses. We showed here that the conserved elements in the viral genomic …


Peptides And Metalloproteins: Evolution, Catalysis And Material Design, Dona Imanga Upamadi Edirisinghe Dec 2024

Peptides And Metalloproteins: Evolution, Catalysis And Material Design, Dona Imanga Upamadi Edirisinghe

Dissertations - ALL

Peptide hydrogels are an important class of biomaterials that have gained significant attention in recent years. The stimuli responsive materials change their properties in response to pH, redox, temperature and enzymes and this property allowed us to design the materials with tunable properties based on their end application. This dissertation reports the de novo design, synthesis and characterization of short chain peptide sequences and optimizations of those in order to develop them into potential candidates in wound care and drug delivery applications. The investigation of these novel peptide sequences will open up new possibilities to tailor the properties through simple …


Molten Flux Synthesis Of Plutonium (Iv) Silicates K2Pusi2O7 And Rb2Pusi6O15, Travis K. Deason, Gregory Morrison, Amir Mofrad, Jake Amoroso, David Diprete, Theodore M. Besmann, Shanna L. Estes, Hans Conrad Zur Loye Dec 2024

Molten Flux Synthesis Of Plutonium (Iv) Silicates K2Pusi2O7 And Rb2Pusi6O15, Travis K. Deason, Gregory Morrison, Amir Mofrad, Jake Amoroso, David Diprete, Theodore M. Besmann, Shanna L. Estes, Hans Conrad Zur Loye

Faculty Publications

Few plutonium containing silicates have been reported in the literature and only one other tetravalent plutonium silicate structure has been reported using the flux growth method. With the goal of understanding actinide incorporation into silicates, we describe herein two new plutonium (IV) silicates, Rb2PuSi6O15 and K2PuSi2O7, synthesized using a mixed alkali chloride/alkali fluoride flux growth. Both structures crystallize in the C2/c space group with lattice parameters a=24.2980(10) Å, b=7.1466(3) Å, c=17.2025(8) Å and 96.6560(10)° for Rb2PuSi6O15, and a=9.9478(2) Å, b=5.59820 (10) Å, c=13.1848(2) Å, and 105.7400(10)° for K2PuSi2O7. Comparisons to the synthesis of other reported alkali actinide silicates (Ce, U, …


Assembly Of Ppsu-Oligomers, Mariam Nesterov Dec 2024

Assembly Of Ppsu-Oligomers, Mariam Nesterov

Student Theses and Dissertations

The development of nanostructures for delivering multiple proteins to targeted antibodies has become a promising avenue in biotechnology, driven by advancements in synthetic polymers like poly(propylene sulfone), PPSU. However, the PPSU polymer faces a major limitation - its high insolubility. To address this challenge, this study investigates whether PPSU oligomers can enhance both the solubility and stability of lysozyme, a model protein that is cost-effective and widely accessible. Using dimer, trimer, tetramer, and hexamer configurations, we analyzed the interactions between PPSU oligomer and lysozyme under varying conditions. Our results show that the dimer and trimer are water soluble (no aggregate …


Intrinsic Gas-Phase Behavior Of Uranium Species: A Comprehensive Reactivity Study Of [O=U≡Ch]+ And [Uh]+, Justin Terhorst Dec 2024

Intrinsic Gas-Phase Behavior Of Uranium Species: A Comprehensive Reactivity Study Of [O=U≡Ch]+ And [Uh]+, Justin Terhorst

Electronic Theses and Dissertations

The intrinsic chemistry of actinide elements, particularly uranium, remains a key challenge in understanding f-block reactivity due to the complexity introduced by solvent interactions, counter-ions, and complex equilibria in the condensed phase. In this dissertation, a systematic gas-phase study utilizing preparative tandem ion-trap mass spectrometry (PTMSn) is presented, focusing on the reactivity of uranium-centered species, specifically [OUCH]+, an oxy uranium methylidyne species, and [UH]+ ions. By stripping away solvent effects and isolating the ions, PTMSn provides a powerful platform to probe the fundamental chemical behavior of uranium species in their intrinsic state.

The …


Modulating Liquid-Liquid Phase Separation Of Intrinsically Disordered Proteins Through Lipidation, Zhe Zhang Dec 2024

Modulating Liquid-Liquid Phase Separation Of Intrinsically Disordered Proteins Through Lipidation, Zhe Zhang

Dissertations - ALL

Liquid-liquid phase separation (LLPS) is a fascinating biological phenomenon that enables cells to form membraneless organelles, creating specialized compartments for orchestrating complex biochemical reactions. While significant progress has been made in deciphering the sequence determinants underlying phase separation, precisely modulating these features remains a challenge. Inspired by biology, post-translational modifications (PTMs) offer a promising approach to modulate the protein condensates formation and their properties in real-time, without altering the sequences. Despite the identification of over 300 types of PTMs, most research has predominantly focused on charge-altering modifications. The effects of non-charged PTMs, such as lipidation, on LLPS remain poorly understood. …


An In-Depth Analysis And Comparison Of Eco And Non-Eco Surfboard Waxes, Markos Kaskaneas - Efthymiou Dec 2024

An In-Depth Analysis And Comparison Of Eco And Non-Eco Surfboard Waxes, Markos Kaskaneas - Efthymiou

The Plymouth Student Scientist

Questions regarding the sustainability of petroleum-based surfboard waxes gave rise to the development and marketing of a sustainable alternative called “Eco” surf wax. The chemistry behind surf waxes is generally unknown and there is no published research on the area of surf waxes. In this analysis, the chemical properties of both types of waxes were investigated, to determine the difference between non-eco and eco waxes and between different water temperature rating waxes. 15 surf wax samples (10 non-eco, 5 eco) were extracted into organic and inorganic fractions and analysed by FT-IR, GC-MS, and HTGC-FID/MS. Multivariate statistical analysis was also performed. …


Synthesis And Characterisation Of An Acetylcholinesterase Inhibitor, Elijah Rahman-Riding Dec 2024

Synthesis And Characterisation Of An Acetylcholinesterase Inhibitor, Elijah Rahman-Riding

The Plymouth Student Scientist

Acetylcholinesterase (AChE) inhibitors are currently the only effective treatment for people with Alzheimer’s disease (AD), a fatal neurodegenerative disease that affects 50 million people worldwide at present but is expected to rise dramatically over the next 30 years. The aim of this research was to synthesise an AChE inhibitor derivative of tacrine, 4-chloro-2(((1,2,3,4-tetrahydroacridin-9yl)imino)methyl)phenol (chlorophenol tacrine). This was achieved by first synthesising tacrine, evidencing successful synthesis and assaying purity of the product, then, synthesising a simple derivative, acetyl tacrine, before chlorophenol tacrine. At every stage of the investigation comprehensive structural analysis of each product was obtained using FT-IR, CHN analysis, GC-FID, …


Development Of Methods For Predicting Second Harmonic Generation (Shg) Responses Of New Infrared Nonlinear Optical (Ir-Nlo) Materials, Katherine Colbaugh Dec 2024

Development Of Methods For Predicting Second Harmonic Generation (Shg) Responses Of New Infrared Nonlinear Optical (Ir-Nlo) Materials, Katherine Colbaugh

Electronic Theses and Dissertations

Dissertation supervised by Dr. Jennifer A. Aitken.

In this work, calculations-based methods were evaluated for use in prediction of second harmonic generation (SHG), specifically χ(2) values, of infrared nonlinear optical (IR-NLO) materials. Net dipole moment and dipole moment per volume were calculated by the bond valence sum method. Average F-index, proposed in this research, and group F-index, both representing induced dipole moment were also calculated. Each calculation was evaluated by comparing the results to single crystal and powder χ(2) measurements of IR-NLO materials. The selected dataset consisted of ninety-six compounds including polar and nonpolar structures, newly discovered and …


Rna Structural-Dynamical Hierarchy: Sars-Cov, Sars-Cov-2, And Delta/Omicron Variant S2m Monomers, Kissing Complexes, And Extended Duplexes, Adam Kensinger Dec 2024

Rna Structural-Dynamical Hierarchy: Sars-Cov, Sars-Cov-2, And Delta/Omicron Variant S2m Monomers, Kissing Complexes, And Extended Duplexes, Adam Kensinger

Electronic Theses and Dissertations

The power and promise of ribonucleic acid (RNA) molecules are only beginning to be realized in living organisms and pharmaceutical intervention. Specifically, defining the chemical physics of RNA’s heterogenous structural ensemble and dynamics, which has experienced expansive growth over the last few years, is central to a complete understanding, yet continues to be a significant challenge. A 41-nucleotide hairpin called the stem-loop II motif (s2m), present in the viral genomes of severe acute respiratory syndrome (SARS), SARS-coronavirus-2 (SARS-CoV-2), and the Delta and Omicron variants responsible for the COVID-19 pandemic, is a potential antiviral target due to its high sequence conservation …


Synthesis, Characterization, And Investigation Of Photochemical And In Vitro Properties Of Novel Zn(Ii) Phthalocyanine, Yasemi̇n Bayğu Yildiz, Ni̇lgün Kabay, Burak Yildiz, İpek Ömeroğlu, Mahmut Durmuş, E. Riza Karagür, Hakan Akça, Çağri Ergi̇n, Yaşar Gök Dec 2024

Synthesis, Characterization, And Investigation Of Photochemical And In Vitro Properties Of Novel Zn(Ii) Phthalocyanine, Yasemi̇n Bayğu Yildiz, Ni̇lgün Kabay, Burak Yildiz, İpek Ömeroğlu, Mahmut Durmuş, E. Riza Karagür, Hakan Akça, Çağri Ergi̇n, Yaşar Gök

Turkish Journal of Chemistry

In our work, a new non-peripheral zinc(II) phthalocyanine bearing octa carboxylic acid ethyl ester derivative substituted triazole attached propylmercaptothiobenzylmercapto derivative was synthesized by the tetramerization reaction of phthalonitrile. The photochemical in vitro photodynamic activity of zinc(II) phthalocyanine (ZnPc-I), such as human non-small cell lung carcinoma cell lines, was investigated in this study. The singlet oxygen generation property of novel zinc(II) phthalocyanine (ZnPc-I) was also examined due to the significantly high singlet oxygen quantum yield of ZnPc-I (ΦΔ = 0.66). The antiproliferative effects of ZnPc-I were also investigated on A549 and H1299 cell lines, our results demonstrate that the ZnPc-I has …


Synthesis, Structure, Hirshfeld Surface Analysis, And Molecular Docking Studies Of The Cocrystal Between The Cu(Ii) Complex Of Salicylic Acid And Uncoordinated Piracetam, Nazokat N. Yuldasheva, Ikram I. Abdullaev, Oybek I. Khudoyberganov, Lola A. Gandjaeva, Pirnazar K. Kodamboev, Elyor Sh. Samandarov, Adkhamjon S. Normamatov, Abror Kh. Ruzmetov, Yuldosh Y. Yakubov, C. Balakrishnan, Bakhtiyar T. Ibragimov, Aziz Bakhti̇yarovich Ibragimov Dec 2024

Synthesis, Structure, Hirshfeld Surface Analysis, And Molecular Docking Studies Of The Cocrystal Between The Cu(Ii) Complex Of Salicylic Acid And Uncoordinated Piracetam, Nazokat N. Yuldasheva, Ikram I. Abdullaev, Oybek I. Khudoyberganov, Lola A. Gandjaeva, Pirnazar K. Kodamboev, Elyor Sh. Samandarov, Adkhamjon S. Normamatov, Abror Kh. Ruzmetov, Yuldosh Y. Yakubov, C. Balakrishnan, Bakhtiyar T. Ibragimov, Aziz Bakhti̇yarovich Ibragimov

Turkish Journal of Chemistry

The cocrystal or supramolecular complex between Cu(II) complex of salicylic acid and uncoordinated piracetam has been synthesized. Its structure is characterized by element analysis, FT-IR, UV-Visible spectroscopy and X-ray crystallography. Spectroscopic methods confirm the formation of the metal complex while X-ray crystallography establishes molecular and crystal structure of the obtained compound. Binuclear Cu(II) complex of salicylic acid (complex molecule) is in the form of “Chinese lantern” and it interacts with uncoordinated piracetam by complicated system of H-bonds. However, according to the Hirshfeld surface analysis a contribution of the O•••H/H•••O contacts is only 24.9% while H•••H and H•••C/C•••H contacts account for …


Preparation Of Manganese-Doped Carbon Quantum Dots@Halloysite Nanotubes Composites Films For Advanced Uv Shielding Properties, Xiao Zhang, Bin Wang Dec 2024

Preparation Of Manganese-Doped Carbon Quantum Dots@Halloysite Nanotubes Composites Films For Advanced Uv Shielding Properties, Xiao Zhang, Bin Wang

Turkish Journal of Chemistry

The development of Ultraviolet (UV) shielding materials are of great importance to protect human's health concerns and prevent the degradation of organic matters. However, the synthesis of highly efficient UV shielding polymer nanocomposites is currently limited by the agglomeration of inorganic anti-UV nanoparticles (NPs) within the polymer matrix and limited absorption spectrum of UV shielding agents. In this study, highly effective manganese doped carbon quantum dots@halloysite nanotubes composites (Mn-CDs@HNTs/PAS) were successfully synthesized by loading manganese doped carbon quantum dot (Mn-CDs) into UV shielding effective halloysite nanotubes (HNTs) via solvothermal method, followed by polymerization modification. The results show that inorganic NPs …


A Fast And Responsive Turn-On Fluorescent Probe Based On A Quinone Conjugated Alkoxy Derivative For Biothiols And A Cellular Imaging Study, Ulviyye Nemetova, Ayşe Nur Önem, Alev Er, Sefa Çeli̇k, Ayşen E. Özel, Sevi̇m Akyüz, Mustafa Özyürek, Si̇bel Şahi̇nler Ayla Dec 2024

A Fast And Responsive Turn-On Fluorescent Probe Based On A Quinone Conjugated Alkoxy Derivative For Biothiols And A Cellular Imaging Study, Ulviyye Nemetova, Ayşe Nur Önem, Alev Er, Sefa Çeli̇k, Ayşen E. Özel, Sevi̇m Akyüz, Mustafa Özyürek, Si̇bel Şahi̇nler Ayla

Turkish Journal of Chemistry

Detection of intracellular biothiols (cysteine (CYS), N-acetyl cysteine (NAC) and glutathione (GSH)) with high-selectivity and sensitivity is important to reveal biological functions. In this study, 2-(2-methoxy-4-methylphenoxy)-3-chloro-5,8-dihydroxynaphthalene-1,4-dione (3) (DDN-O) compound was newly synthesized and used as a fluorogenic probe (detector molecule) in the fluorometric method for the rapid, highly selective and sensitive determination of biothiols. The intensity values (λex = 260 nm, λem = 620 nm) of the product were measured by adding biotihols to the reaction medium at varying concentrations and the glutathione equivalent thiol content (GETC) values of each biotiol were calculated. Using the compoud (3), the reference biotiol …


Understanding Ammonia's Role In Mitigating Concentration Polarization In Anion-Exchange Membrane Electrodialysis, Abdallah Timmaoui, Mahmoud Ferhat, Nesri̇ne Souad Ferhat, Ahmed Hamdi Dec 2024

Understanding Ammonia's Role In Mitigating Concentration Polarization In Anion-Exchange Membrane Electrodialysis, Abdallah Timmaoui, Mahmoud Ferhat, Nesri̇ne Souad Ferhat, Ahmed Hamdi

Turkish Journal of Chemistry

In processes such as electrodialysis, the applied electrical potential is constrained by concentration polarization at the membrane/solution interface. This polarization, which intensifies at higher current densities, impedes ion transport efficiency and may lead to problems such as salt precipitation, membrane degradation, and increased energy consumption. Therefore, understanding concentration polarization is essential for enhancing membrane performance, improving efficiency, and reducing operational costs. This study investigates the impact of ammonia buffer (NH₄⁺/NH₃) on sulfate ion transport through anion-exchange membranes, with a particular focus on limiting current density and concentration polarization under constant current conditions. Our findings demonstrate that ammonia effectively eliminates concentration …


Capacity-Weighted Figures-Of-Merit For Battery Transport Metrics, Cj Sturgill, Christopher Sutton, Julian Schwenzel, Morgan Stefik Dec 2024

Capacity-Weighted Figures-Of-Merit For Battery Transport Metrics, Cj Sturgill, Christopher Sutton, Julian Schwenzel, Morgan Stefik

Faculty Publications

New battery materials with improved transport are needed. Typical measurements yield widely varying voltage-dependent diffusivities and reporting practices are diverse. Some materials (e.g. first-order phase change) have most redox occur at a specific voltage and may be sufficiently represented by singular transport metrics. Many rapid intercalation materials, however, exhibit second-order phase transitions with redox over a broad voltage range. How should such cases be compared? The use of capacity-weighted average values is suggested where voltage-dependent metrics are consolidated into representative descriptors as figures-of-merit. Examples are elaborated where differential capacity (dQ/dV) is used to derive a …


Synthesis Of Higher-Order Catenanes And Catenane-Based Materials, Gray Harlan Dec 2024

Synthesis Of Higher-Order Catenanes And Catenane-Based Materials, Gray Harlan

Arts & Sciences Graduate Student Theses and Dissertations

Catenanes are a subset of mechanically interlocked molecules (MIMs) and are composed of interlocked rings that can be oriented linearly, radially, or branched. A defining feature of all MIMs is that they are bound through their architectures consisting of mechanical bonds, leading to unique topologies. Catenanes have attracted interest due to their stimuli-responsive behavior and the degrees of freedom afforded by the mechanical bond, a feature which is absent with standard covalent bonds. The stimuli responsiveness of catenanes arises from their templated syntheses, where two or more pre-macrocycles are brought together by a driving force. Various templation strategies rely on …


Utility Of Immobilized Metal Salens As Electrocatalysts: Fuel Cells And Organic Electrosynthesis, Zachary A. Nguyen, Shelley D. Minteer Dec 2024

Utility Of Immobilized Metal Salens As Electrocatalysts: Fuel Cells And Organic Electrosynthesis, Zachary A. Nguyen, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

There have been significant advancements in the electrosynthesis of fuels and organic molecules, making it an increasingly sustainable and cost-effective alternative to traditional chemical redox reagents. Early versions of these systems faced challenges in chemo selectivity due to high applied overpotentials, which have been mitigated with the introduction of molecular electrocatalysts, like metal salens (MSalens). These MSalens reduce the required overpotentials, increase turnover numbers (TON), and have simple modularity within their ligand structure allowing for tunable selectivity. While these MSalen electrocatalysts are typically used homogeneously for engineering simplicity, downstream separations are often costly and time-consuming. Immobilization of MSalens addresses these …


Synergistic Adsorption Of Pb (Ii) From Aqueous Solution Using Calcined Biochar-Bentonite Clay Hybrid, Azeezat Faderera Abdul-Raheem Dec 2024

Synergistic Adsorption Of Pb (Ii) From Aqueous Solution Using Calcined Biochar-Bentonite Clay Hybrid, Azeezat Faderera Abdul-Raheem

Theses and Dissertations

The biochar-bentonite clay hybrid was prepared by coprecipitation with the goal of producing a material that can remove Pb (II) from aqueous solutions effectively. Incorporating bentonite clay onto the Douglas fir biochar (DFB-BTC) surface significantly improved the adsorption capacity by introducing more active sites, strengthening the structural properties, and promoting strong adsorbate interactions. The point of zero charge of the adsorbent was slightly higher than that of the pristine DFBC. All sorption experiments were performed at pH 5, and the system obeyed the Langmuir adsorption isotherm. The highest Langmuir adsorption capacities observed at 298, 308, and 318 K were 48, …


Impact Of Cascading Optical Processes On Spectroscopic Quantification Of Absorption And Scattering Properties Of Samples, Pathum Dilshan De Silva Wathudura Dec 2024

Impact Of Cascading Optical Processes On Spectroscopic Quantification Of Absorption And Scattering Properties Of Samples, Pathum Dilshan De Silva Wathudura

Theses and Dissertations

Light absorption and scattering are fundamental properties of matter, particularly significant in nanoscale materials. This study explores how cascading optical processes affect the experimental measurement of absorption and scattering intensities, along with scattering depolarization, in samples containing absorbers and scatterers. The experimental UV–vis spectrum results from the combination of absorption and scattering extinction spectra. However, the maximum measurable extinction may be limited by forward scattered light. Light absorption decreases the intensity of scattered light and influences scattering depolarization. While scattering can reduce absorption along the optical path to the detector, sufficient absorption of the scattered light may counterbalance this effect, …


Engineering Functionalized Nanomaterials For Targeting And Ablating Biofilms On Surfaces, Dhanush Lakmal Yapa Amarasekara Dec 2024

Engineering Functionalized Nanomaterials For Targeting And Ablating Biofilms On Surfaces, Dhanush Lakmal Yapa Amarasekara

Theses and Dissertations

Biofilms on both the surface and interior of medical devices pose major challenges, including hindering device performance and serving as infection sources. These biofilms form a protective layer around bacteria, shielding them from the body’s immune system and antibiotics. This makes infections difficult to treat, as the bacteria within the biofilm are resistant to both antibiotics and immune defenses. Additionally, biofilms can induce inflammation and irritation in nearby tissues, leading to further health complications. Antibiotic resistance raises concerns about the emergence of multi-drug resistant (MDR) pathogens. MDR infections are difficult to treat, leading to prolonged hospital stays and the need …


Investigation Of Real-Time Gaseous Thermal Decomposition Products Of Representative Per- And Polyfluoroalkyl Substances (Pfas), Kateřina Litvanová, Bethany Klemetstrud, Feng Xiao, Alena Kubatova Dec 2024

Investigation Of Real-Time Gaseous Thermal Decomposition Products Of Representative Per- And Polyfluoroalkyl Substances (Pfas), Kateřina Litvanová, Bethany Klemetstrud, Feng Xiao, Alena Kubatova

Chemistry Faculty Publications

The thermal decomposition of per- and poly fluoroalkyl substances (PFAS) is poorly understood. Here, we present an innovative, comprehensive analytical method to investigate their thermal decomposition, including perfluorocarboxylic acids (PFCAs), alcohol, sulfonates, and GenX (acid dimer), focusing on identifying their breakdown products. In this study, evolved gas analysis–mass spectrometry (EGA-MS) was used for fast real-time screening to determine the significant temperatures to be investigated with the thermal desorption-pyrolysis coupled with gas chromatography–mass spectrometry (TD-Py-GC-MS), which provided detailed information about evolved PFAS and their breakdown products. This approach enabled a systematic study of perfluorocarboxylic acids (PFCAs) ranging from C3 to …


Exfoliated Hydrotalcite-Transition Metal Complex Composite For Eco-Friendly And Efficient Catalytic Degradation Of 4-Nitrophenol, Sidra Khan, Najma Memon, Saima Q. Memon, Yilmaz Yurekli Dec 2024

Exfoliated Hydrotalcite-Transition Metal Complex Composite For Eco-Friendly And Efficient Catalytic Degradation Of 4-Nitrophenol, Sidra Khan, Najma Memon, Saima Q. Memon, Yilmaz Yurekli

Karbala International Journal of Modern Science

Nitrophenols are notorious aquatic organic contaminants found as degradation products of various parent compounds, including pesticides and industrial chemicals that persist in the environment and must be removed. Catalytic degradation is one of the feasible routes to clean the contaminated water systems, however, environmental contamination with catalysts is also widespread. Herein, we report an environmentally friendly catalyst based on composited Fe-Schiff’s base with exfoliated layered double hydroxides (LDH) of aluminum and nickel (hydrotalcite). The composite showed agglomerated pleated LDH structures sheathed with Fe(III)SB. Nitrogen adsorption isotherm data exhibited improved surface area and narrow pores patterns for composite as compared to …


Physical Properties Of Aqueous Imide-Based Electrolyte Solutions, Mollie Harr Dec 2024

Physical Properties Of Aqueous Imide-Based Electrolyte Solutions, Mollie Harr

Honors Capstones

In order to observe the effects that cations have on the physical properties of -TFSI [-bis(trifluoromethane sulfonyl)imide] based salts, four salts (LiTFSI, NaTFSI, Mg(TFSI)2, and Al(TFSI)3) were selected for testing. The data gathered shows that when the anion is large and bulky like -TFSI, the size of the cation does not have a large effect on the physical properties, but the oxidation state of the cation may have a significant effect. The ion-ion interactions, such as collisions, aggregation, and repulsion are more significant when the cation has a higher oxidation state due to the increased ratio of anion per molecule …