Chemistry Commons^™

First-Principles Study Of Ferroelectric Properties And Co2 Reduction Reaction Capabilities In Two-Dimensional Monolayers And Heterostructures, Mo Li

Dissertations

Two-dimensional (2D) materials hold significant potential for CO₂ reduction reactions (CO₂RR) due to their high surface-to-volume ratio. However, achieving high selectivity for desired products and overcoming limitations posed by scaling relationships remain challenging. Recent studies suggest that ferroelectric (FE) materials with switchable out-of-plane polarization (OOP) can effectively tune the adsorption behavior, thermodynamics, and kinetics of CO₂RR, offering promising solutions to these challenges. Using density functional theory (DFT) and the Berry phase approach, this work expands the family of 2D ferroelectrics by theoretically identifying Y₂CO₂, Y₂CS₂, and Sc …

Design Of Motivational-Realistic-Pancasila Learning In Mathematics, Marup Marup, Suradi Tahmir, Ahmad Talib, Nurzatulshima Kamaruddin

Jurnal Pendidikan Sains

Learning mathematics in class greatly influences students' learning success both in terms of knowledge and attitudes. In carrying out learning, a learning design is needed that can foster student motivation so that they provide learning outcomes to the learning objectives. Motivational-Realistic-Pancasila learning design is considered to be an alternative solution. Morela is a design that combines motivational, realistic indicators and Pancasila values. The teaching of mathematics in the classroom significantly influences students' academic success, both in terms of knowledge and attitude. To effectively carry out the teaching process, a well-designed instructional approach is necessary to foster students' motivation to achieve …

The Radical Oxidation Of Hydroxyacetone: An Insight Into The Reaction Mechanism And Potential Tetraoxide Intermediates, Edward Buck

Master's Theses

This thesis presents the reaction of hydroxyacetone, a common volatile organic compound (VOC), with chlorine radicals in the presence of oxygen. Chapter one explores VOCs and their specific reactions and how tetraoxide intermediates could be formed from them. Chapter two analyses the experimental and computational methods used and the key theoretical concepts behind these methods. Experimental data was collected using multiplexed photoionization mass spectrometry at the Advanced Light Source Chemical Transformations Beamline, Lawrence Berkeley National laboratory. This data is combined with theoretical data using the CBS-QB3 composite method to determine the key reaction intermediates and mechanisms.

The main chapter of …

Single-Step Synthesis Of Activated Carbon From Arabica Spent Coffee Ground Using K2co3 As Activator Agent, Ghina Ivana Mieldan, Yuliusman Yuliusman

Journal of Materials Exploration and Findings

Activated carbon is a nanomaterial that is often used as an effective adsorbent. Activated carbon raw materials can use biomass, such as coffee grounds, which can be found along with the growth of public interest in coffee drinks. Chemical activators are used for activation to increase biomass carbon's adsorption capacity. Using K₂CO₃ activator to increase the specific surface area of activated carbon is more harmless than KOH. The use of spent coffee grounds as carbon source and food additive K₂CO₃ as an activator can make food-grade activated carbon that can be used for food. …

Effect Of Alkyd And Polyester Resin Compositions On Corrosion Resistance, Blistering, And Adhesion In Utilization Of Oily Sludge As Anti-Rust Coating Material, Gerets Land Kakalang, Yohanes David Kristianto, Johny Wahyuadi Mudaryoto

Journal of Materials Exploration and Findings

Oil sludge is a waste derived from upstream and downstream activities of the oil and gas industry which is estimated at 10,000 tonnes generated from all PERTAMINA downstream activities spread across various fields, processing units and depots throughout Indonesia. Oil sludge has the same characteristics as asphalt, where asphalt in previous studies can be used as an anti-rust coating, so that the handling of oily sludge can be topped up by reusing and having its own added value. The purpose of this research is to utilise waste oily sludge as an alternative anti-rust coating material and compare alkyd resin and …

Development Of Conceptual Scaffolding-Assisted Formative Assessment For Enhancing Understanding Of Temperature And Heat, Ana Lailatul Fitriyah, Sentot Kusairi, Markus Diantoro

Jurnal Pendidikan Sains

This research aims to develop formative assessment media assisted by conceptual scaffolding to improve students’ understanding of temperature and heat, test its validity and practicality, and gauge student responses. Utilizing the ADDIE model, the research follows five stages: Analysis, Design, Development, Implementation, and Evaluation. In the Analysis stage, a literature review was conducted to identify critical components, including formative assessment, conceptual scaffolding, concept mastery, and previous research. The Design stage involved identifying users, defining competencies and indicators, creating a storyboard, integrating assessment components, and determining mastery levels. During the Development stage, the assessment media were developed into a functional product. …

Composite Volume Learning Media Based On Augmented Reality To Enhance Students’ Visual-Spatial Intelligence, Ria Kurniawati, Susiswo Susiswo, Syamsul Hadi

Jurnal Pendidikan Sains

Augmented Reality (AR) technology, a three-dimensional visual tool that integrates virtual objects or environments into real-world displays in real time (Azuma et al., 2001), is particularly useful for grasping complex concepts such as the composite volume of solids, which often confuses students when they need to decompose solids into their individual components. While previous research has predominantly focused on the introduction of solids, spatial nets, and the volume of singular shapes, this study aims to develop composite volume learning media based on AR to enhance students’ visual-spatial intelligence in a valid, practical, and effective manner, aligning with their concrete operational …

Students’ Concept Maps Profile On Environmental Pollution Material During The Covid-19 Pandemic, Sunarni Sunarni, Sri Widoretno, Puguh Karyanto, Bowo Sugiharto, Sri Dwiastuti, Chandra Adi Prabowo

Jurnal Pendidikan Sains

The study investigates the performance of students in constructing Concept Maps (CM) related to environmental pollution material during the COVID-19 pandemic. The data reveals that the overall achievement in CM construction was suboptimal, with no component reaching more than half of its maximum potential. The highest achievement was recorded in the valid relationship component, which attained 9.75% of its maximum possible score. This was followed by the hierarchy component, achieving 7.34%, and the branching component at 3.42%. The pattern component ranked fourth with 1.31%, closely followed by the example component at 1.30%. The lowest performance was observed in the crosslink …

Analysis Of Students’ Problem-Solving Skills In Newton’S Law With 5e Learning Cycle, Nidya Desyana, Sutopo Sutopo, Nandang Mufti

Jurnal Pendidikan Sains

The aim of this study is to identify students’ problem-solving skills in Newton’s laws through the implementation of the 5E learning cycle in the classroom. A pre-experimental design with a one-group pretest-posttest approach was employed. Data on problem-solving skills were collected from students’ pre-test and post-test responses to two essay questions. The indicator with the highest percentage of problem-solving skills was useful description (83% of students), while the indicator with the lowest percentage was specific application of physics (33% of students). Due to the non-normal distribution of the data, the Wilcoxon test was utilized. The results indicated a significant difference …

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 …

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 SnO_x encapsulation layer on the surface of Pt NPs can protect Pt NPs from the poisoned of CO impurity in …

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.

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 …

Muramyl Peptide Blend Ameliorates Intestinal Inflammation And Barrier Integrity In Caco-2 Cells, Dmytro M. Masiuk, Victor S. Nedzvetsky, Giyasettin Baydas

Karbala International Journal of Modern Science

Intestinal barrier function depends on epithelial adhesion, which restricts permeability and microbial invasion from the internal environment. Impairment of barrier integrity and gut function is closely linked to pro-inflammatory changes. Inflammation is often the primary factor that provokes gut function disorders. The anti-inflammatory potential of postbiotics has been reported in recent years. Muramyl peptides (MPs) are small signaling molecules that stimulate intracellular pathogen receptors and can regulate cell responses. However, the molecular mechanisms of MPs' effects on intestinal cells remain unknown. The study of MPs treatment on lipopolysaccharide (LPS)-challenged Caco-2 intestinal cells aimed to investigate the postbiotic effects on intestinal …

Potential Health Risks From Trace Elements In Four Commercially Important Fish Species From The Gulf Of Alaska And Bering Sea Excel Data Sheet, Miranda Brohman, Dimtirios Giarikos, Amy Hirons

SECLER Data

Alaskan waters support a diverse array of fish species that are critical to apex predators and substantial commercial fisheries. Archived white lateral muscle tissue for capelin, herring, walleye pollock, and Pacific cod, from 1993 to 1996 were analyzed for 15 trace elements using induced coupled plasma mass spectrometry. This analysis serves as a proxy for assessing trace element concentrations in the Gulf of Alaska and Bering Sea. The highest concentrations of eight of the 15 elements (cadmium, chromium, cobalt, iron, manganese, selenium, vanadium, and zinc) were found in fish from the central Gulf of Alaska, while capelin showed the …

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

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

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 …

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, …

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 …

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

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 …

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 …

Synthetic Studies On Ship Activators And New Oxidative Methods Utilizing Ddq And Hypervalent Iodine Catalysts, Christos Nixarlidis

Dissertations - ALL

One important cell signaling pathway is the PI3K pathway because it influences many key cellular functions such as proliferation and apoptosis. Among the enzymes that are involved in this pathway, the SH2-containing inositol-5’-phosphatase (SHIP) plays an important role by maintaining the balance of PI(3,4,5)P3 and PI(3,4)P2. SHIP activation promotes a higher rate of hydrolysis of PI(3,4,5)P3 and thus reduces the downstream activation of AKT, which influences many cell processes. Activation of SHIP using small molecules may be useful for certain diseases such as inflammatory disorders and some types of cancer. The synthesis and evaluation of a new class of sulfonamide …

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

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. …

Developing A Method To Identify Tyre Particles By Detecting Benzothiazole Via Gc-Ms, Emma Paull

The Plymouth Student Scientist

Tyre particles are a dominant source of microplastic pollution in our environment. However, their chemical and physical properties are poorly understood and no standardised methods for identifying and quantifying them exist. This study looked to develop a method to identify tyre particles using two tyre samples of differing particle sizes, fine (62 - 125 µm) and coarse (250 – 500 µm). Both samples underwent ultrasound-assisted extraction before being analysed via gas chromatography-mass spectrometry (GC-MS) in both full scan and SIM mode, using benzothiazole as a marker. Both samples were also analysed via particle size analysis, scanning electron microscopy (SEM) and …

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, …

Application Of Two-Directional Carbonyl Ene Reaction To The Synthesis Of Complex Tetrahydropyrans, And Studies Toward The Synthesis Of C26-C39 Subunit Of Spirastrellolide B., Md Abid Abid Hasan

Dissertations - ALL

The use of exocyclic enol ethers as nucleophiles in carbon-carbon bond forming reactions has been underutilized in organic synthesis. This work describes the use of 6-iodomethyl-2-methylenetetrahydropyran as a bis-exocyclic enol ether equivalent for the synthesis of pyran derivatives. Use of this linchpin allows for bidirectional elaboration of the pyran core by two directional carbonyl ene. The development of a convergent, modular synthesis of 2,6-disubstituted-4H-pyrans in a three-step sequence starting from 6-iodomethyl-2-methylenetetrahydropyran is described. Initial carbonyl ene reaction of 6-iodomethyl-2-methylenetetrahydropyran with aldehydes or activated ketones was followed by elimination of iodide to give cross oriented bis-enol ethers that contain both endocyclic …

Studies Towards The Synthesis Of A Simplified Forskolin Core And Phomactin A, Fortune Ononiwu

Dissertations - ALL

Oxadecalins are privileged scaffolds found in various natural products that show biological activity, such as platelet aggregating factor antagonism and activation of adenyl cyclase. As such, various synthetic methods such as intramolecular substitution reactions and [4+2] cycloadditions have been developed for the construction of these important intermediates. Studies towards the synthesis of a simplified core of the labdane diterpene, forskolin, are described. Forskolin is the only known supplement to naturally raise cAMP levels, thereby displaying important pharmacological properties. The synthetic route described features a Lewis acid catalyzed dihydropyrone Diels-Alder reaction for rapidly assembly of the ABC tricycle. Modified Saegusa-Ito oxidation …