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A Work Towards A Single-Bridge Hydrazine Sensor, Brenden Jay Schmeltz Oct 2023

A Work Towards A Single-Bridge Hydrazine Sensor, Brenden Jay Schmeltz

Theses and Dissertations

Hydrazine can currently be detected by irreversible methods, Carbazolopyridinophane (2,18-Dithia[3][1,8]carbazolo[3][2,6]pyridinophane) CP was synthesized by Brown et al. to detect hydrazine in real-time while also being reversible. The threshold for detection was 100 ppb, regulatory use requires 10 ppb as this is when permanent damage to humans can be caused. A more sensitive sensor will allow for safer workplaces for many people. A single, 3-atom bridge sensor will further examine the photophysical capabilities of carbazole-pyridine as an emitter/quencher pair. 1-Carbazole-1-methylpyridyl-2methyl sulfide SBCP will allow freedom of rotation as well as the bending of the bridge. These benefits will introduce conformers which …


Enhanced Cell Viability And Migration Of Primary Bovine Annular Fibrosus Fibroblast-Like Cells Induced By Microsecond Pulsed Electric Field Exposure, Prince M. Atsu, Connor Mowen, Gary L. Thompson Iii Sep 2023

Enhanced Cell Viability And Migration Of Primary Bovine Annular Fibrosus Fibroblast-Like Cells Induced By Microsecond Pulsed Electric Field Exposure, Prince M. Atsu, Connor Mowen, Gary L. Thompson Iii

Henry M. Rowan College of Engineering Departmental Research

This study is the first to report the enhancement of cell migration and proliferation induced by in vitro microsecond pulsed electric field (μsPEF) exposure of primary bovine annulus fibrosus (AF) fibroblast-like cells. AF primary cells isolated from fresh bovine intervertebral disks (IVDs) are exposed to 10 and 100 μsPEFs with different numbers of pulses and applied electric field strengths. The results indicate that 10 μs-duration pulses induce reversible electroporation, while 100 μs pulses induce irreversible electroporation of the cells. Additionally, μsPEF exposure increased AF cell proliferation up to 150% while increasing the average migration speed by 0.08 μm/min over 24 …


Exploring The Correlation Between Metacognitive Skills And Cognitive Learning Outcomes Across Various Biology Learning Models In High Schools, Ninik Kristiani, Herawati Susilo, Aloysius Duran Corebim, Fatchur Rohman Sep 2023

Exploring The Correlation Between Metacognitive Skills And Cognitive Learning Outcomes Across Various Biology Learning Models In High Schools, Ninik Kristiani, Herawati Susilo, Aloysius Duran Corebim, Fatchur Rohman

Jurnal Pendidikan Sains

In Malang City, a notable observation within the realm of high school biology education suggests a prevalent lack of metacognitive knowledge among teachers, hindering their efficacy in nurturing students' metacognitive capacities. Such deficiency yields implications for diminished cognitive abilities among students. Recognizing this, there emerges a pressing need for an enhanced pedagogical framework capable of fostering metacognitive skills adeptly. One promising approach involves integrating inquiry-based learning and problem- based mindful pedagogy (PBMP). This amalgamation is anticipated to synergistically harness the potential of both methodologies in bolstering metacognitive skills alongside cognitive learning outcomes. This study adopts a correlational research design, wherein …


Analysis And Unraveling Misconceptions: Examining Tenth-Grade High School Students’ Errors In Hots Questions On Exponential Equations And Effective Scaffolding Strategies, Nunik Indayani, Erry Hidayanto, Sisworo Sisworo Sep 2023

Analysis And Unraveling Misconceptions: Examining Tenth-Grade High School Students’ Errors In Hots Questions On Exponential Equations And Effective Scaffolding Strategies, Nunik Indayani, Erry Hidayanto, Sisworo Sisworo

Jurnal Pendidikan Sains

The objective of this study is to elucidate the errors made by tenth-grade students at SMA Hati Bilingual Boarding School Probolinggo, Indonesia, when tackling Higher Order Thinking Skills (HOTS) questions on exponential equations, along with the scaffolding process employed to mitigate these errors. Employing qualitative research methods, four participants were chosen based on their performance in completing HOTS questions on exponential equations, followed by in-depth interviews. The identified student errors encompass basic errors, appropriate errors, missing information, and partial insights. The analysis aligns these errors predominantly with Brodie’s error taxonomy. Furthermore, the study highlights the efficacy of instructional scaffolding, utilizing …


Analysis Of Student Engagement And Perceptions Of Community Of Inquiry (Coi)-Based Blended Learning In The Chemical Separation Subject On Chromatography, Agita Dzulhajh Anggraini, Surjani Wonorahardjo, Yudhi Utomo Sep 2023

Analysis Of Student Engagement And Perceptions Of Community Of Inquiry (Coi)-Based Blended Learning In The Chemical Separation Subject On Chromatography, Agita Dzulhajh Anggraini, Surjani Wonorahardjo, Yudhi Utomo

Jurnal Pendidikan Sains

Learning in higher education has often been conducted solely through face-to-face, teacher- centered approaches. Implementing Community of Inquiry (CoI)-based blended learning in chromatography is crucial as it offers students a novel learning experience. This pre- experimental study, utilizing a one-group pretest-posttest design, aimed to describe students’ perceptions of CoI-based blended learning in chromatography. Data were collected using a questionnaire comprising 34 statements. The results indicated that students had a neutral perception of CoI-based blended learning. While a community of inquiry has been established, it has not yet reached its full potential, as students have not fully experienced social presence in …


The Identification Of Students’ Conceptual Mastery Of Fluid Statics: An Overview Of Gender, Maria Claudia Sodakain, Sentot Kusairi, Nandang Mufti, Jane Koswojo Sep 2023

The Identification Of Students’ Conceptual Mastery Of Fluid Statics: An Overview Of Gender, Maria Claudia Sodakain, Sentot Kusairi, Nandang Mufti, Jane Koswojo

Jurnal Pendidikan Sains

This study aimed to assess the conceptual mastery of fluid statics among students, employing a descriptive quantitative approach. The research involved 22 male and 13 female students from eleventh-grade MIPA at a private school in Surabaya, Indonesia. The primary research instrument comprised 11 multiple-choice and reasoning questions, covering concepts related to Pressure and Hydrostatic Pressure, Pascal’s Law, and Archimedes’ Principle. Results indicated a higher level of conceptual mastery among male students compared to their female counterparts. While both genders demonstrated relatively high conceptual mastery in Pressure and Hydrostatic Pressure, significant disparities were observed in their understanding of Pascal’s Law and …


Evaluation Of The Inhibitive Properties Of Silver Nanoparticles In Senna Occidentalis Root Extract As Corrosion Inhibitor Of Mild Steel, Victor O. Egbeneje, Samuel E. Okhale, Chinyere Imoisi, Isaac O. Ogbogo, Omolade Ojo Sep 2023

Evaluation Of The Inhibitive Properties Of Silver Nanoparticles In Senna Occidentalis Root Extract As Corrosion Inhibitor Of Mild Steel, Victor O. Egbeneje, Samuel E. Okhale, Chinyere Imoisi, Isaac O. Ogbogo, Omolade Ojo

Tanzania Journal of Science

The use of nanoparticles as corrosion inhibitors has gained popularity because of its increased corrosion efficiency due to increase surface to volume ratio. Nanoparticles which undergo physisorption/chemisorption to the corrosion metal surface and inhibit the corrosion efficiently also have low toxicity, low cost and easy production. In this research work, weight lost method was applied to study the inhibitive properties of silver nanoparticles (AgNPs) synthesized using Senna occidentalis root extract as environmentally benign corrosion inhibitor of mild steel in 0.5 M H2SO4 medium at 298 K and 308 K. It was observed that the corrosion rate of the steel sample …


Microplastics In Marine Sediments From Dar Es Salaam Coast: Spatial Distribution And Characterization, Macarius P. Mtega, Matobola J. Mihale, Kessy F. Kilulya Sep 2023

Microplastics In Marine Sediments From Dar Es Salaam Coast: Spatial Distribution And Characterization, Macarius P. Mtega, Matobola J. Mihale, Kessy F. Kilulya

Tanzania Journal of Science

The purpose of the research was to determine the spatial distribution and characterization of microplastics in marine sediments of beaches along the Indian Ocean of Dar es Salaam coast. The sediment samples were extracted in triplicate using floatation method followed by digestion of organic debris, then analyzed using At-FTIR spectrophotometer and stereomicroscope. The mean concentrations of microplastics for Kijichi Beach were 700 ± 907 particles/m2 at 1 cm, 859 ± 839 particles/m2 at 5 cm and 590 ± 782 particles/m2 at 10 cm; from Palm Beach were 157 ± 15 particles/m2 at 1 cm, 130 ± 182 particles/m2 at 5 …


Optical Characterization Of Photocatalytic Tungsten Oxide/Tin Oxide (〖Wo〗_3/〖Sno〗_2) Thin Films For Use In Degradation Of Water Pollutants, Victor Isahi, Christopher Maghanga, Mghendi Mwamburi, Onesmus Munyati, Sylvester Hatwaambo, Emmanuel Akoto, Wycliffe Isoe, Mir Waqas Alam Sep 2023

Optical Characterization Of Photocatalytic Tungsten Oxide/Tin Oxide (〖Wo〗_3/〖Sno〗_2) Thin Films For Use In Degradation Of Water Pollutants, Victor Isahi, Christopher Maghanga, Mghendi Mwamburi, Onesmus Munyati, Sylvester Hatwaambo, Emmanuel Akoto, Wycliffe Isoe, Mir Waqas Alam

Tanzania Journal of Science

Organic pollutants in water have been a challenge and pose significant risks to human health. As a result, research efforts to eliminate these pollutants have been on the rise. Photocatalysis has shown incredible potential in water treatment containing organic pollutants since it is affordable and utilizes solar energy. Tin oxide ( ) has ardently been investigated as a photocatalyst for water treatment due to its remarkable properties such as; non-toxicity, and stability. However, its wide band gap and the tendency for some electrons and holes to recombine during its use have been cited to be among limiting factors affecting its …


Molecularly Imprinted Electrochemical Sensor Based On Poly (O-Phenylenediamine) For Sensitive Detection Of Oxycodone In Water, Pranaya Charkravarthula, Amos Mugweru Sep 2023

Molecularly Imprinted Electrochemical Sensor Based On Poly (O-Phenylenediamine) For Sensitive Detection Of Oxycodone In Water, Pranaya Charkravarthula, Amos Mugweru

College of Science & Mathematics Departmental Research

This work was aimed at the development of a sensitive electrochemical detection method for oxycodone in water. Molecularly imprinted electrodes were formed by electro-polymerization process using o-phenylenediamine as a monomer. The electro-polymerization was performed on glassy carbon electrodes in the presence of oxycodone before the extraction of entrapped oxycodone molecules. Various electrochemical techniques were employed to monitor the polymerization and response of the fabricated electrodes toward oxycodone. These techniques included cyclic voltammetry (CV), square wave voltammetry (SWV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The oxycodone concentration was determined using SWV by measuring the change in the oxidation …


Hydrophobicity Optimization Of Cathode Catalyst Layer For Proton Exchange Membrane Fuel Cell, Hao-Jie Chen, Mei-Hua Tang, Sheng-Li Chen Sep 2023

Hydrophobicity Optimization Of Cathode Catalyst Layer For Proton Exchange Membrane Fuel Cell, Hao-Jie Chen, Mei-Hua Tang, Sheng-Li Chen

Journal of Electrochemistry

Hydrophobicity of the cathode catalyst layers (CCLs) crucially determines the performance of proton exchange membrane fuel cells (PEMFCs) by affecting the transports of oxygen and liquid water. In this regard, polytetrafluoroethylene (PTFE) is usually used as a hydrophobic additive to facilitate the oxygen and water transports in CCLs. So far, there remains lacking systematic effort to optimize the addition methods of PTFE in CCLs and the mechanisms behind. In this work, the effects of the approaches for PTFE addition and the distribution of PTFE on the mass transport of oxygen and the proton conduction in CCLs were studied by using …


Dependence Of Heat Transfer Model On The Structure Of Electrically Coil-Heated Microelectrodes, Ju Li, Sen Yang, Jian-Jun Sun Sep 2023

Dependence Of Heat Transfer Model On The Structure Of Electrically Coil-Heated Microelectrodes, Ju Li, Sen Yang, Jian-Jun Sun

Journal of Electrochemistry

Electrically heated microelectrodes have gained much attention in electroanalytical chemistry in recent years. It has been shown that the promotion of mass transport and reaction kinetics at high-temperatures often results in increased current signals. However, there is no study about the heat transfer inner the microelectrodes which is necessary for the design and operation for microsensors. This report introduces a finite element software (COMSOL) to analyze the factors that influence the surface temperature (Ts), which is crucial for the heating ability of micro-disk electrodes with coils. Distances between the electrode surface and the bottom of the heated copper …


Fundamental Study Of Ionic Liquid Physicochemical Effects On Thermal Stability Of Model Biological Macromolecules, Austin Keith Clark Sep 2023

Fundamental Study Of Ionic Liquid Physicochemical Effects On Thermal Stability Of Model Biological Macromolecules, Austin Keith Clark

Theses and Dissertations

Ionic Liquids (ILs) are substances with a unique physical attribute compared to that of solid ionic salts. At room temperature, ILs are molten salts that have a variety of physical effects that can play a role in their impact on other molecules, as solvents or solutes. They can play the role of the solvent in a variety of applications, from biofuels to organic catalysis or as excipients in pharmaceutical formulations. These ILs have a desirable use as solvents due to their ability to be tunable substances. Changing the cation or anion of the IL causes a change in its physical …


Phosphorus And Its Role In Chemical Evolution, Asbel Gonzalez Sep 2023

Phosphorus And Its Role In Chemical Evolution, Asbel Gonzalez

PANDION: The Osprey Journal of Research and Ideas

Phosphorus is a minor element with a cosmic abundance of about 105.5 atoms per 1012 H atoms (Boudreaux, n.d.). Phosphorus was depleted as a volatile throughout the developing solar system, and as a result, volatile forms of phosphorus would have been minimal, even in the colder regions of the solar nebula. Despite its low abundance, phosphorus minerals play key roles in planetary petrology, including through the formation of phosphate minerals that trapped volatiles and rare Earth elements, and in the formation of metal phosphides that may have served as nucleation sites for kamacite and taenite crystal growth in minor planet …


Synthesis, Characterization, Antibacterial Activity, And Potential Water Filter Application Of Copper Oxide/Zeolite Composite, Elfa Aida Kamila, Zaenal Abidin, Irma Isnafia Arief, Trivadila Trivadila Sep 2023

Synthesis, Characterization, Antibacterial Activity, And Potential Water Filter Application Of Copper Oxide/Zeolite Composite, Elfa Aida Kamila, Zaenal Abidin, Irma Isnafia Arief, Trivadila Trivadila

Makara Journal of Science

Detection of E. coli bacteria in water samples can indicate the presence of other bacterial contamination in feces. Bacterial contamination can be treated with antibiotics, but excessive use of antibiotics leads to the emergence of multiresistant bacteria. Therefore, alternative antibacterial agents must be explored. Copper ion/zeolite composite has been widely studied as an antibacterial agent. However, the released copper ions accumulate in water and are toxic to humans; this can be prevented by converting copper ions into copper oxides (CuO and Cu2O). In this study, copper oxide/zeolite composite is synthesized and characterized using the heating method, followed by …


Antibacterial Testing On Silver/Zinc Oxide Nanoparticles/Organoclay Reinforced Chitosan Biocomposites, Lisna Junaeni Muiz, Ariadne Lakshmidevi Juwono, Zulkarnaen Paputungan, Yuni Krisyuningsih Krisnandi Sep 2023

Antibacterial Testing On Silver/Zinc Oxide Nanoparticles/Organoclay Reinforced Chitosan Biocomposites, Lisna Junaeni Muiz, Ariadne Lakshmidevi Juwono, Zulkarnaen Paputungan, Yuni Krisyuningsih Krisnandi

Makara Journal of Science

Herein, bionanocomposites of chitosan (CS)/silver nanoparticle/organoclay/zinc oxide nanoparticle (CS/Ag/OC/ZnO) were prepared for antibacterial food packaging. This study examines the time variation in the AgNP synthesis method by comparing local (74˗85% deacetylated) and commercial chitosan (75%˗85% deacetylated) as a reducing and capping agent and seeks to reconstruct the optimum ratio formulations of AgNPs and ZnONPs in bionanocomposites for food packaging. The results reveal that the synthesis of AgNPs was successfully carried out using a local chitosan solution as a reducing and capping agent. The CS/Ag/OC/ZnO films exhibit structural, mechanical, and optical properties suitable for food packaging and antibacterial activity on Staphylococcus …


Eggshell-Alginate Composites (Eacs) As Eco-Friendly Adsorbents For Rhodamine B Uptake From Aqueous Solutions, Rusnadi Rusnadi, Mar’Atus Sholihah, Nurrahmi Handayani, Muhammad Ali Zulfikar Sep 2023

Eggshell-Alginate Composites (Eacs) As Eco-Friendly Adsorbents For Rhodamine B Uptake From Aqueous Solutions, Rusnadi Rusnadi, Mar’Atus Sholihah, Nurrahmi Handayani, Muhammad Ali Zulfikar

Karbala International Journal of Modern Science

The contamination of wastewater by Rhodamine B (RhB) poses a significant environmental concern due to its negative impacts on aesthetics, ecosystems, and human well-being. This study successfully synthesized eco-friendly egg-shell-alginate composites (EACs) as adsorbents by combining alginate solution, eggshell powder, and a 2% CaCl2 solu-tion. Characterization techniques including FTIR, SEM, TGA, and SAA were employed to analyze the EACs. FTIR analysis revealed characteristic absorption peaks corresponding to -OH groups, C=O groups, C-O groups, and the pres-ence of CO32-. The structural analysis confirmed the physical mixture of functional groups from eggshells and alginate, resulting in a homogeneous EACs mixture. TGA analysis …


Synthesizing Of Alginate Coated-Silver Nanoparticles Core-Shell For Detecting Of S-Naproxen Enantiomer In Pharmaceutical Formulation, Abdolrasol Barazandeh, Ghasem Najafpour-Darz, Afshar Alihossein, Sohrab Kazemi Sep 2023

Synthesizing Of Alginate Coated-Silver Nanoparticles Core-Shell For Detecting Of S-Naproxen Enantiomer In Pharmaceutical Formulation, Abdolrasol Barazandeh, Ghasem Najafpour-Darz, Afshar Alihossein, Sohrab Kazemi

Karbala International Journal of Modern Science

Core-shell nanoparticles were used in a unique direct UV-Vis spectrophotometric technique to detect the S-naproxen enantiomer. Silver nanoparticles (Ag NPs) covered with sodium alginate (Alg) shell, a naturally occurring biopolymer, made the core of the nanostructure. To name a few, TEM, FESEM, UV-Visible, DLS, ZP, AFM, XRD, EDX and FT-IR are among the analytical methods used to analyze the creation of the core-shell structure. Based on obtained results, spherical Ag@ Alg NPs with an average size of 27.4 nm (DTEM), hydrolytic size of 46 nm (DDLS) and surface charge of -60.9 mV were successfully synthesized. The effect of various reaction …


Time-Resolved Cryo-Em (Tr-Em) Analysis Of Substrate Polyubiquitination By The Ring E3 Anaphase-Promoting Complex/Cyclosome (Apc/C), Tatyana Bodrug, Kaeli A. Welsh, Derek L. Bolhuis, Ethan Paulаkonis, Raquel C. Martinez-Chacin, Bei Liu, Nicholas Pinkin, Thomas Bonacci, Liying Cui, Pengning Xu, Olivia Roscow, Sascha Josef Amann, Irina Grishkovskaya, Michael J. Emanuele, Joseph S. Harrison, Joshua P. Steimel, Klaus M. Hahn, Wei Zhang, Ellen D. Zhong, David Haselbach, Nicholas G. Brown Sep 2023

Time-Resolved Cryo-Em (Tr-Em) Analysis Of Substrate Polyubiquitination By The Ring E3 Anaphase-Promoting Complex/Cyclosome (Apc/C), Tatyana Bodrug, Kaeli A. Welsh, Derek L. Bolhuis, Ethan Paulаkonis, Raquel C. Martinez-Chacin, Bei Liu, Nicholas Pinkin, Thomas Bonacci, Liying Cui, Pengning Xu, Olivia Roscow, Sascha Josef Amann, Irina Grishkovskaya, Michael J. Emanuele, Joseph S. Harrison, Joshua P. Steimel, Klaus M. Hahn, Wei Zhang, Ellen D. Zhong, David Haselbach, Nicholas G. Brown

Pacific Faculty Work

Substrate polyubiquitination drives a myriad of cellular processes, including the cell cycle, apoptosis and immune responses. Polyubiquitination is highly dynamic, and obtaining mechanistic insight has thus far required artificially trapped structures to stabilize specific steps along the enzymatic process. So far, how any ubiquitin ligase builds a proteasomal degradation signal, which is canonically regarded as four or more ubiquitins, remains unclear. Here we present time-resolved cryogenic electron microscopy studies of the 1.2 MDa E3 ubiquitin ligase, known as the anaphase-promoting complex/cyclosome (APC/C), and its E2 co-enzymes (UBE2C/UBCH10 and UBE2S) during substrate polyubiquitination. Using cryoDRGN (Deep Reconstructing Generative Networks), a neural …


Anharmonic Ir Absorption Spectra Of The Prototypical Interstellar Pahs Phenanthrene, Pyrene, And Pentacene In Their Neutral And Cation States, Vincent J. Esposito, Louis J. Allamandola, Christiaan Boersma, Jesse D. Bregman, Ryan C. Fortenberry, Alexandros Maragkoudakis, Pasquale Temi Sep 2023

Anharmonic Ir Absorption Spectra Of The Prototypical Interstellar Pahs Phenanthrene, Pyrene, And Pentacene In Their Neutral And Cation States, Vincent J. Esposito, Louis J. Allamandola, Christiaan Boersma, Jesse D. Bregman, Ryan C. Fortenberry, Alexandros Maragkoudakis, Pasquale Temi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Combination band and overtone transitions of polycyclic aromatic hydrocarbon (PAH) cations in the 2000–2900 cm-1 (5-3.5 µm) region are implicated as carriers of the ‘quasi-continuum’ observed in the near-infrared (IR) emission spectra of many astronomical objects. In neutral PAHs, the strongest absorption features are concentrated in the 700–900 cm-1 (14–11 µm) range, which are associated with CH out-of-plane bending motions. Upon ionization, this shifts to the 1000–1600 cm-1 (10–6 µm) range, where bands are associated with C=C stretches and CH in-plane bends. Anharmonicity is required to accurately characterize the IR absorption spectrum of PAHs, indicated herein by …


Mechanistic Investigations Of A Novel Braf Regulatory Switch And Braftide, An Allosteric Peptide Inhibitor Of Braf, Alison Yu Sep 2023

Mechanistic Investigations Of A Novel Braf Regulatory Switch And Braftide, An Allosteric Peptide Inhibitor Of Braf, Alison Yu

Theses and Dissertations

RAF kinases (ARAF/BRAF/CRAF or Raf-1) are serine/threonine kinases in the MAPK (RAS-RAF-MEK-ERK) pathway. The MAPK pathway is crucial in development and normal cell function. These same roles are dysregulated in cancer; BRAF is the most frequently mutated isoform in cancers and in particular, activation loop mutants BRAF V600E/K mutants have the highest mutational incidence. Three FDA approved inhibitors potently inhibit BRAF V600E/K mutants. However, these same inhibitors fail to address the non-V600E/K mutations and result in paradoxical activation of the MAPK pathway. Two strategies were employed to address the limitations of the FDA-approved inhibitors: provide novel regulatory details of RAF …


Hydrogen Peroxide Disproportionation Activity Is Sensitive To Pyridine Substitutions On Manganese Catalysts Derived From 12-Membered Tetra-Aza Macrocyclic Ligands, David M. Freire, Hannah M. Johnston, Katherine J. Smith, Kristof Pota, Magy A. Mekhail, Sugam Kharel, Kayla N. Green Sep 2023

Hydrogen Peroxide Disproportionation Activity Is Sensitive To Pyridine Substitutions On Manganese Catalysts Derived From 12-Membered Tetra-Aza Macrocyclic Ligands, David M. Freire, Hannah M. Johnston, Katherine J. Smith, Kristof Pota, Magy A. Mekhail, Sugam Kharel, Kayla N. Green

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The abundance of manganese in nature and versatility to access different oxidation states have made manganese complexes attractive as catalysts for oxidation reactions in both biology and industry. Macrocyclic ligands offer the advantage of substantially controlling the reactivity of the manganese center through electronic tuning and steric constraint. Inspired by the manganese catalase enzyme, a biological catalyst for the disproportionation of H2O2 into water and O2, the work herein employs 12-membered tetra-aza macrocyclic ligands to study how the inclusion of and substitution to the pyridine ring on the macrocyclic ligand scaffold impacts the reactivity of …


Approaches To Assessing Nutrient Coupling In Open Ocean Datasets, James M. Moore, Claire P. Till Sep 2023

Approaches To Assessing Nutrient Coupling In Open Ocean Datasets, James M. Moore, Claire P. Till

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

Nutrient coupling describes a process where the biogeochemical cycles of two elements are linked by being incorporated similarly into biomass. This paper uses data from the GEOTRACES GP16 cruise (Eastern Pacific Zonal Transect) to investigate the relationship between certain macronutrients generally coupled to trace elements in terms of their oceanic distributions with the notable exception of in an oxygen minimum zone: cadmium-phosphate and zinc-silicate. There are many methods applied to oceanographic data to correlate analyte concentrations; while they are often presented independently in literature, here we attempt to use them in conjunction for a more thorough interpretation. By compiling 1) …


Microplastics In Water, Their Effects On The Aquatic Ecosystem And Human Public Health, And The Proposed Solutions, Mohanad Abouserie Sep 2023

Microplastics In Water, Their Effects On The Aquatic Ecosystem And Human Public Health, And The Proposed Solutions, Mohanad Abouserie

The Undergraduate Research Journal

We could be swallowing a credit card's weight in plastic every week. Microplastic water pollution is becoming a threat to both humans and aquatic creatures. In this research, microplastic water contamination is discussed, and divergent solutions are proposed. This paper attempts to investigate the causes and effects of such pollution and analyze the current solutions for this issue. The adopted research method is secondary research, where several studies are explored and analyzed. This study explains numerous causes for this issue like cosmetics, cleaning products, factories, and sewage. Consequently, this contamination can negatively impact the organs and metabolisms of the living …


Phenyl Acrylate-Based Cross-Linked Anion Exchange Membranes For Non-Aqueous Redox Flow Batteries, Md Motiur R. Mazumder, Rohit G. Jadhav, Shelley D. Minteer Sep 2023

Phenyl Acrylate-Based Cross-Linked Anion Exchange Membranes For Non-Aqueous Redox Flow Batteries, Md Motiur R. Mazumder, Rohit G. Jadhav, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Redox flow batteries (RFBs) are of recent interest to store harvested renewable energy for improving grid reliability and utilization. in this study, we synthesized and characterized a series of phenyl acrylate-Based UV-cross-linked anion exchange membranes (AEMs) and explored the performance of these AEMs in a model non-aqueous RFB under model conditions. Infrared spectroscopy was utilized to confirm the incorporation of ion carriers in the phenyl acrylate backbone. the electrochemical performance was compared with the commercial Fumasep membrane Fuma-375 based on high stability in non-aqueous solvents, high permeability to the charge-carrying ion, low resistance, low crossover of the redox-active molecules, and …


From Random To Rational: Improving Enzyme Design Through Electric Fields, Second Coordination Sphere Interactions, And Conformational Dynamics, Shobhit S. Chaturvedi, Daniel Bím, Christo Christov, Anastassia N. Alexandrova Sep 2023

From Random To Rational: Improving Enzyme Design Through Electric Fields, Second Coordination Sphere Interactions, And Conformational Dynamics, Shobhit S. Chaturvedi, Daniel Bím, Christo Christov, Anastassia N. Alexandrova

Michigan Tech Publications

Enzymes are versatile and efficient biological catalysts that drive numerous cellular processes, motivating the development of enzyme design approaches to tailor catalysts for diverse applications. In this perspective, we investigate the unique properties of natural, evolved, and designed enzymes, recognizing their strengths and shortcomings. We highlight the challenges and limitations of current enzyme design protocols, with a particular focus on their limited consideration of long-range electrostatic and dynamic effects. We then delve deeper into the impact of the protein environment on enzyme catalysis and explore the roles of preorganized electric fields, second coordination sphere interactions, and protein dynamics for enzyme …


Solvatochromic And Aggregation-Induced Emission Active Nitrophenyl-Substituted Pyrrolidinone-Fused-1,2-Azaborine With A Pre-Twisted Molecular Geometry, Albert D. Campbell Jr., Kaia Ellis, Lyric K. Gordon, Janiyah E. Riley, Robert B. Hughley, Adeline M. Boswell, Ophelia Adjei-Sah, Prioska D. Baruah, Ra’Nya Malone, Carl Saint-Louis Sep 2023

Solvatochromic And Aggregation-Induced Emission Active Nitrophenyl-Substituted Pyrrolidinone-Fused-1,2-Azaborine With A Pre-Twisted Molecular Geometry, Albert D. Campbell Jr., Kaia Ellis, Lyric K. Gordon, Janiyah E. Riley, Robert B. Hughley, Adeline M. Boswell, Ophelia Adjei-Sah, Prioska D. Baruah, Ra’Nya Malone, Carl Saint-Louis

Faculty Articles

Boron–nitrogen-containing heterocycles with extended conjugated π-systems such as polycyclic aromatic 1,2-azaborines, hold the fascination of organic chemists due to their unique optoelectronic properties. However, the majority of polycyclic aromatic 1,2-azaborines aggregate at high concentrations or in the solid-state, resulting in aggregation-caused quenching (ACQ) of emission. This practical limitation poses significant challenges for polycyclic aromatic 1,2-azaborines’ use in many applications. Additionally, only a few solvatochromic polycyclic aromatic 1,2-azaborines have been reported and they all display minimal solvatochromism. Therefore, the scope of available polycyclic 1,2-azaborines needs to be expanded to include those displaying fluorescence at high concentration and in the solid-state as …


Poly(Propylene Glycol)-Based Non-Isocyanate Polyurethane Ionenes: Thermal, Morphological And Conductive Properties, Jordan C. Pierce, George M. Timmermann, Creston Singer, David Salas-De La Cruz, Kevin Miller Sep 2023

Poly(Propylene Glycol)-Based Non-Isocyanate Polyurethane Ionenes: Thermal, Morphological And Conductive Properties, Jordan C. Pierce, George M. Timmermann, Creston Singer, David Salas-De La Cruz, Kevin Miller

Faculty & Staff Research and Creative Activity

The synthesis and characterization of a series of polyurethane ionenes using a non-isocyanate approach is disclosed. Imidazole-capped, urethane-containing prepolymers are prepared by first reacting carbonyl diimidazole (CDI) with several poly(propylene glycol) (PPG) diols with variable molecular weight, followed by subsequent reaction with 3-aminopropylimidazole (API). Polymerization with 1,4-dibromomethylbenzene followed by anion exchange resulted in the desired polyurethane ionenes bearing the [NTf2] counteranion as a series of viscous liquids. NMR and FTIR spectroscopy are used to characterize the intermediates and final ionenes, including molecular weight determination by end-group analysis. A single glass transition temperature (Tg), as determined by differential scanning …


Multiple Structural And Functional Annotations Based In-Silico Characterization Of Q9brx8 Protein, Eiman Zahid, Muhammad Farhan Sarwar Sep 2023

Multiple Structural And Functional Annotations Based In-Silico Characterization Of Q9brx8 Protein, Eiman Zahid, Muhammad Farhan Sarwar

Karbala International Journal of Modern Science

Numerous proteins found in humans are poorly understood because there is a dearth of experimental evidence. Hypothetical proteins (HPs) or uncharacterized proteins are the terms used to describe these proteins. In this work, one of these proteins, Q9BRX8, is investigated using in-silico or bioinformatics tools to reveal its significant properties. In this regard, NCBI for the sequence retrieval, ProtParam tool for analysis of physiochemical properties, SOPMA for secondary structure prediction, SWISS-Model for homology modelling, STRING for protein-protein interaction and HDOCK for protein-protein docking analysis among other tools, were incorporated. The physiochemical characteristics indicated that Q9BRX8, which has an instability score …


Investigations On Copper Assisted Oxidative Transformations For The Construction Of Diverse C-C/C-N(O) Bonds, Prasanna Kumari S Sep 2023

Investigations On Copper Assisted Oxidative Transformations For The Construction Of Diverse C-C/C-N(O) Bonds, Prasanna Kumari S

Theses and Dissertations

Copper catalyzed C-C, C-N/C-O bond formation reactions are a prominent tool to access diverse biologically relevant molecules. Herein, we present the copper- catalyzed diverse C-C/C-N(O) bond forming reactions. In Chapter-I (introduction), we briefly discussed the various copper mediated organic transformations with appropriate examples.

In Chapter II, we report a one-pot methodology for the vicinal aminoalkylation of naphthoquinone through a direct C(sp2)-H functionalization reaction. Through this method, readily available planar naphthoquinone substrates were transformed into three-dimensional molecular scaffolds through the formation of one C(sp2)-C(sp2) and two C(sp2)-N bonds. The indole fused nitrogen heterocyclic products were obtained in good yields. Apart from …