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Deciphering The Interdomain Coupling In A Gram-Negative Bacterial Membrane Insertase, Adithya Polasa, Shadi A. Badiee, Mahmoud Moradi

Chemistry & Biochemistry Faculty Publications and Presentations

YidC is a membrane protein that plays an important role in inserting newly generated proteins into lipid membranes. The Sec-dependent complex is responsible for inserting proteins into the lipid bilayer in bacteria. YidC facilitates the insertion and folding of membrane proteins, both in conjunction with the Sec complex and independently. Additionally, YidC acts as a chaperone during the folding of proteins. Multiple investigations have conclusively shown that Gram-positive bacterial YidC has Sec-independent insertion mechanisms. Through the use of microsecond-level all-atom molecular dynamics (MD) simulations, we have carried out an in-depth investigation of the YidC protein originating from Gram-negative bacteria. This …

Synthesis Of Amorphous And Various Phase-Pure Nanoparticles Of Nickel Phosphide With Uniform Sizes Via A Trioctylphosphine-Mediated Pathway, David Thompson, Adam S. Hoffman, Zachary R. Mansley, Sarah York, Feng Wang, Yimei Zhu, Simon R. Bare, Jingyi Chen

Chemistry & Biochemistry Faculty Publications and Presentations

Nickel phosphides are of particular interest because they are highly active and stable catalysts for petroleum/biorefinery and hydrogen production. Despite their significant catalytic potential, synthesizing various phase-pure nickel phosphide nanoparticles of uniform size remains a challenge. In this work, we develop a robust trioctylphosphine (TOP)-mediated route to make highly uniform phase-pure Ni₁₂P₅, Ni₂P, and Ni₅P₄ nanoparticles. The synthetic route forms amorphous Ni₇₀P₃₀ nanoparticle intermediates. The reactions can be stopped at the amorphous stage when amorphous particles are desired. The amount of P incorporation can be controlled by varying …

Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt pavements make up a majority of the essential transportation systems in the US. Asphalt mixtures age and degrade over time, reducing the pavement performance. Pavement performance critically depends on the aging of asphalt binder. The aging of asphalt binder during construction is traditionally modeled by rolling thin film oven (RTFO) testing, while aging during service life is modeled by pressure aging vessel (PAV) testing. Comparing these models to the aging of binders in actual pavements is limited because, to be used for current testing, binders must be separated from the pavement's aggregate by solvent extraction. Solvent extraction will, at …

Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt pavements make up a majority of the essential transportation systems in the US. Asphalt mixtures age and degrade over time, reducing the pavement performance. Pavement performance critically depends on the aging of asphalt binder. the aging of asphalt binder during construction is traditionally modeled by rolling thin film oven (RTFO) testing, while aging during service life is modeled by pressure aging vessel (PAV) testing. Comparing these models to the aging of binders in actual pavements is limited because, to be used for current testing, binders must be separated from the pavement's aggregate by solvent extraction. Solvent extraction will, at …

Nuclear Magnetic Resonance (Nmr) Assessment Of Bio And Crude Oil-Based Rejuvenation, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binders in pavements lose their stability through aging and eventually fail in the field. Using nuclear magnetic resonance (NMR) to monitor the primary longitudinal relaxation time of asphalt samples and the ratio of material that carries this primary relaxation time has been shown to indicate the impact of ultraviolet (UV) radiation on the aging of asphalt pavements. Longitudinal NMR relaxation was used to investigate two types of proposed asphalt rejuvenators, a bio-oil-based rejuvenator and a crude-oil-based rejuvenator. Two different binders with the performance grades (PG) 64-22 and 76-22 were considered for their interactions with the rejuvenators. After 72 h …

Drying Techniques For Precooked Hybrid Rice To Ensure Quality Of Instantized Rice, Anne Adhiambo Okeyo, Kaushik Luthra, Justin Siebenmorgen, Alan R. Vazquez, Griffiths Atungulu

Food Science Faculty Publications and Presentations

Background and Objectives

Due to the emergence of new hybrid rice cultivars, rice processors must refine their processing protocols to maintain the production of high-quality products. This is crucial for the instant rice processing industry. Therefore, this study aims to refine current convective heated air-drying processing methods to suit the new hybrid rice cultivars intended for instant rice production. New strategies to dry cooked rice were investigated. These included drying in a stepwise manner with high (230–200°C) and medium (190–160°C) air temperatures and drying at constant high (200°C) and medium (160°C) air temperatures. Changes in quality attributes of two new …

Structural, Electronic And Magnetic Properties Of Vanadium Doped Transition Metal Dichalcogenides (Tmds), Qudsia Ashraf

Dissertations, Theses, and Capstone Projects

Magnetic semiconductors are a prerequisite for spintronic devices but their ferromagnetism disappears at room-temperature hindering application in room temperature electronic devices. Enormous research has been conducted on the room-temperature ferromagnetic order in monolayer form of bulk van der Waals materials but the few layer system has not been extensively explored.

Doping is an effective approach to modulate the structural, electronic and magnetic properties of two-dimensional (2D) Transition metal dichalcogenides (TMDs) and expand their application. The effect of vanadium dopant on structural, electronic and magnetic properties of Tungsten Diselenide (WSe₂) was studied by X-ray Photoelectron Spectroscopy (XPS), Atomic Force …

Electrified Membrane For Water Treatment And Resource Recovery: Advancing Multiscale Strategies In Gas-Involving Reactions, Jianan Gao

Dissertations

Multifunctional, modular, and scalable water treatment technologies that operate without chemical additives are crucial for addressing global water pollution challenges. While traditional membrane-based separation processes are crucial for ensuring clean water supplies, they primarily focus on pollutant removal rather than on the upcycling of pollutants into valuable resources. Electrified membrane filtration presents a robust alternative, utilizing minimal or no chemical additives and harnessing electrical power to directly reduce contaminants or produce reactive oxidants or reductants on-site.

This dissertation is dedicated to the development of innovative electrochemically reactive membranes designed to address three major challenges: (1) the engineering of electrocatalysts with …

Recent Advances On Ruthenium-Based Electrocatalysts For Lithium-Oxygen Batteries, Yu-Zhe Wang, Zhuo-Liang Jiang, Bo Wen, Yao-Hui Huang, Fu-Jun Li

Journal of Electrochemistry

Rechargeable lithium-oxygen (Li-O₂) batteries have attracted wide attention due to their high energy density. However, the sluggish cathode kinetics results in high overvoltage and poor cycling performance. Ruthenium (Ru)-based electrocatalysts have been demonstrated to be promising cathode catalysts to promote oxygen evolution reaction (OER). It facilitates decomposition of lithium peroxide (Li₂O₂) by adjusting Li₂O₂ morphologies, which is due to the strong interaction between Ru-based catalyst and superoxide anion (O₂^–) intermediate. In this review, the design strategies of Ru-based electrocatalysts are introduced to enhance their OER catalytic kinetics in …

Numerical Analysis Of Explosion Characteristics Of Vent Gas From 18650 Lifepo4 Batteries With Different States Of Charge, Shi-Lin Wang, Xu Gong, Li-Na Liu, Yi-Tong Li, Chen-Yu Zhang, Le-Jun Xu, Xu-Ning Feng, Huai-Bin Wang

Journal of Electrochemistry

The combustion and explosion characteristics of lithium-ion battery vent gas is a key factor in determining the fire hazard of lithium-ion batteries. Investigating the combustion and explosion hazards of lithium-ion batteries vent gas can provide guidance for rescue and protection in explosion accidents in energy storage stations and new energy vehicles, thereby promoting the application and development of lithium-ion batteries. Based on this understanding and combined with previous research on gas production from lithium-ion batteries, this article conducted a study on the combustion and explosion risks of vent gas from thermal runaway of 18650 LFP batteries with different states of …

2024 "Electrochemical Research Paradigms" Summer School Successfully Held, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Upcoming Meeting-The 1St Young Investigator Symposium On Electrosynthesis, Chinese Chemical Society, Chinese Society Of Electrochemistry (Cse)

Journal of Electrochemistry

No abstract provided.

Rate Law For Photoelectrochemical Water Splitting Over Cuo, Bo-Yuan Gao, Wen-Hua Leng

Journal of Electrochemistry

Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen. However, the determination of rate law is rarely reported. To this purpose, copper oxide (CuO) is selected as a model photocathode in this study, and the photogenerated surface charge density, interfacial charge transfer rate constant and their relation to the water reduction rate (in terms of photocurrent) were investigated by a combination of (photo)electrochemical techniques. The results showed that the charge transfer rate constant is exponential-dependent on the surface charge density, and that the photocurrent equals to the product of the charge transfer rate constant …

Winning Results Of The 2Nd Xiamen University Short Video Abstract Contest For Science And Technology Papers, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Winning Works From Journal Of Electrochemistry: The 2Nd Xiamen University Short Video Abstract Contest For Science And Technology Journal Papers, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

2024 World Fuel Cell Conference Held In Ningbo, Zhejiang, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Generative A.I.-Assisted Organic Chemistry Tutoring, Ji Kim

Open Educational Resources

By utilizing tools like ChatGPT, the project aims to provide detailed explanations, answer student questions, and assist with problem-solving, thereby creating a more interactive and personalized learning experience. This approach will help students grasp complex topics more effectively and improve their overall performance in chemistry.

Improvement Of Single-Crystal Structures Of Very Heavy Element Compounds By Refining Anomalous Dispersion Parameters, Florian Meurer, Gregory Morrison, Birgit Hischa, Hans Conrad Zur Loye, Christoph Hennig, Michael Bodensteiner

Faculty Publications

Refining the anomalous dispersion parameters of the four uranium compounds NaUF5, NaU2F9, Cs2(UO2)TiO4, and Cs2(UO2)Ti2O6 gave insights into the crystallographic model improvement of very heavy atoms. We found that the values for the dispersive and absorptive parts, f′ and f″, closely followed the X-ray absorption spectra on their L3, L2, and L1 edges. The obtained values are sensitive to the chemical environment at each crystallographically independent position. An incorrect treatment of the anomalous dispersion correction can lead to a wrong crystallographic model. The above-mentioned, already published structures were improved by this process. General guidelines were given for the crystal structure …

Carbon-Sulfur Bond Elongation As The Promoting Reaction Coordinate In The Efficient Sub-Nanosecond Intersystem Crossing In Thianaphthene Derivatives, Cameron Griffith, Erqian Mao, Sean J. Hoehn, Sarah E. Krul, Carlos E. Crespo-Hernández

Faculty Scholarship

Thiophene derivatives have become integral to OLEDs, photovoltaics, and photodynamic therapy research. A deeper understanding of their excited state dynamics and electronic relaxation mechanisms is expected to provide important physical insights of direct relevance for these applications. In this study, thianaphthene (TN), 2-methylbenzothiophene (2MBT), and 3-methylbenzothiophene (3MBT) are investigated using femtosecond broadband transient absorption and steady-state spectroscopy techniques along with time-dependent density functional calculations in cyclohexane and acetonitrile. The photophysical properties and electronic relaxation mechanisms of these derivatives are elucidated. Small fluorescence quantum yields ranging from 0.4 to 1.1% are measured. It is demonstrated that excitation of TN at 290 …

Investigating The Cellular Localization, Trafficking, And Biological Function Of Ghrelin O-Acyltransferase, Sadie Xiao Hua Novak

Dissertations - ALL

Ghrelin O-acyltransferase (GOAT) catalyzes the acylation and activation of ghrelin, a peptide hormone involved in a range of physiological pathways and therapeutic target for metabolism-linked diseases such as obesity and diabetes. GOAT was determined to be localized in the membrane of the endoplasmic reticulum (ER) in early cell-based studies, but recent patient studies detected this integral membrane enzyme in blood plasma and urine. These findings challenge the current understanding of GOAT’s cellular localization, and it may provide a potential mechanism for ghrelin re-acylation by plasma membrane-resident GOAT. The work described in this dissertation aimed to define the intracellular trafficking mechanism …

An Online Nanoinformatics Platform Empowering Computational Modeling Of Nanomaterials By Nanostructure Annotations And Machine Learning Toolkits., Tong Wang, Daniel P Russo, Philip Demokritou, Xuelian Jia, Heng Huang, Xinyu Yang, Hao Zhu

College of Science & Mathematics Departmental Research

Modern nanotechnology has generated numerous datasets from in vitro and in vivo studies on nanomaterials, with some available on nanoinformatics portals. However, these existing databases lack the digital data and tools suitable for machine learning studies. Here, we report a nanoinformatics platform that accurately annotates nanostructures into machine-readable data files and provides modeling toolkits. This platform, accessible to the public at https://vinas-toolbox.com/, has annotated nanostructures of 14 material types. The associated nanodescriptor data and assay test results are appropriate for modeling purposes. The modeling toolkits enable data standardization, data visualization, and machine learning model development to predict properties and bioactivities …

Application Of A Novel Plasma-Based Advanced Oxidation Process For Efficient And Cost-Effective Destruction Of Refractory Organics In Tertiary Effluents And Contaminated Groundwater, Itay Even-Ezra, Anat Mizrahi, Daniel Gerrity, Shane A. Snyder, Andrew Salveson, Ori Lahav

Civil and Environmental Engineering and Construction Faculty Research

Corona discharge is emerging as a promising advanced oxidation process (AOP) for the treatment of a variety of organic contaminants, including compounds that are not effectively destroyed by more common AOPs. This paper presents laboratory and field results describing the destruction of regulated and Contaminant Candidate List (CCL) compounds in tertiary treated wastewater effluent and contaminated groundwater during the operation of a novel hydro-non-thermal-plasma (HNTP) AOP system. The system generates a plasma discharge above the target water matrix, which emits an “electron wind”, ultraviolet (UV) irradiation, O_3(g) and hydroxyl radicals (•OH) into a relatively thin water layer. The synergism …

Preparation Of A Chiral Hyperbranched Polymer Based On Cinchona Alkaloids And Investigation Of Its Catalytic Activity In Asymmetric Reactions, Rafiqul Islam, Mohammad Shahid Ullah, Abdus Salam, Shinichi Itsuno

Turkish Journal of Chemistry

Cinchona alkaloid-derived sulfonamides and ester dimers containing chiral hyperbranched polymers have been successfully synthesized and applied as catalysts in asymmetric reactions. Several hyperbranched polymers derived from cinchona alkaloids, incorporating sulfonamides and esters, were synthesized through Mizoroki–Heck coupling polymerization. These polymers were subsequently applied in enantioselective Michael addition reactions. As the prepared polymers are not soluble in frequently used organic solvents, they act as efficient catalysts in the enantioselective reaction of β-ketoesters to nitroolefins, achieving up to 99% enantioselectivity with good yields. The insoluble property allows them to better satisfy “green chemistry” requirements and be used several times without losing the …

Liquefaction Optimization Of Grape Pulp Using Response Surface Methodology For Biopolyol Production And Bio-Based Polyurethane Foam Synthesis, Furkan Çolakoğlu, Emre Akdoğan, Murat Erdem

Turkish Journal of Chemistry

Both environmental and economic disadvantages of using petroleum-based products have been forcing researchers to work on environmentally friendly, sustainable, and economical alternatives. The purpose of this study is to optimize the solvothermal liquefaction process of grape pomace using response surface methodology coupled with a central composite design. After investigating the physicochemical properties of the liquified products (biopolyol) in detail, a bio-based rigid polyurethane foam (RPUF) was synthesized and characterized. The hydroxyl and acid numbers and viscosity values of all the biopolyols were analyzed. According to variance analysis results (%95 confidence range), both the reaction temperature and catalyst loading were determined …

New Imidazolidindionedioximes And Their Pt(Ii) Complexes: Synthesis And Investigation Of Their Antitumoral Activities On Breast Cancer Cells, Emrah Karahan, Tuğba Gençoğlu Katmerli̇kaya, Emel Önal, Aydan Dağ, Ayşe Gül Gürek, Vefa Ahsen

Turkish Journal of Chemistry

Breast cancer is one of the most common types of cancer worldwide and has the most lethality ratio for females among all cancers. Although current cancer therapeutics have made considerable advancements, there is still room for improvement in terms of efficacy. Many anticancer drugs have a risk of causing serious adverse effects due to their non-specific cytotoxic effects on both tumor and healthy cells. New therapeutics might have a greater ability to kill cancer cells, reduce the volume of tumors, and improve overall therapy response rates. Herein, we report the efficient synthesis and characterization of three amphi vic-dioximes and their …

Synthesis Of 3-Methyl-3-Buten-1-Ol By Supercritical Co2 In Coordination With Hzsm-5 Catalyzed Formaldehyde-Isobutene Prins Reaction, Hang Yuan, Gui-Ping Cao, Hui Lv

Turkish Journal of Chemistry

The reaction solvent and catalyst play an essential role in the Prins reaction for the synthesis of 3-methyl-3-buten-1-ol (MBO) from formaldehyde and isobutene. The reactivity of the solid base catalyzed Prins condensation reaction by formaldehyde and isobutene in supercritical CO2 was investigated using CsH2PO4 modified HZSM-5. We finds that the alkaline sites of the alkali-loaded catalyst can extract the α-H on isobutene to generate olefin carbon negative ions, while the supercritical CO2 with weak Lewis acidity can activate formaldehyde to carbon positive ions, which can combine more easily with the carbon negative isobutene to react, thus improving the reactivity of …

Magnetic Solid-Phase Extraction Technique Based On Fe3o4@Coppy-Pth Nanocomposite For Extraction Of Cobalt, Chromium, And Nickel Prior To Determination By Micro-Sample Injection System-Flame Atomic Absorption Spectrometry In Alcoholic And Nonalcoholic Beverages, Meli̇ke Küçüksakalli, Qamar Salamat, Buket Ti̇reli̇, Şükrü Gökhan Elçi̇

Turkish Journal of Chemistry

A novel Fe3O4@coPPy-PTH nanocomposite-based sorbent was prepared via in-situ oxidative polymerization using Fe3O4 nanoparticles with spherical and flower-like morphologies of thiophene and pyrrole as the feedstocks. The synthesized nanocomposite utilized sensitive extraction and determination of the metal ions Co(II), Cr(III), and Ni(II) without a chelating agent, followed by a micro-sample injection system-flame atomic absorption spectrometer (MIS-FAAS). The composition and morphology of Fe3O4@coPPy-PTH nanocomposite were characterized by advanced spectroscopic and imaging techniques like SEM and FT-IR. SEM observations showed the size of Fe3O4 nanoparticles changed from 30 nm to 120 nm in diameter after the copolymer (PPy-PTH) coating. The Fe3O4@coPPy-PTH nanocomposite …

Β-Ketoenamine-Linked Covalent Organic Framework For Efficient Iodine Capture, Onur Büyükçakir

Turkish Journal of Chemistry

Exploring the materials that effectively capture radioactive iodine is crucial in managing nuclear waste produced from nuclear power plants. Herein, a β-ketoenamine-linked covalent organic framework (bCOF) was reported as an effective adsorbent to capture iodine from both vapor and solution. bCOF's high porosity and heteroatom-rich skeleton offer a notable iodine vapor uptake capacity of up to 2.51 g g-1 at 75 oC under ambient pressure. Furthermore, after five consecutive adsorption-desorption cycles, the bCOF demonstrates a high reusability performance with a significant iodine vapor capacity retention. The adsorption mechanism was also investigated using various ex-situ structural characterization techniques, and these mechanistic …

Lacoo3 Is A Promising Catalyst For Dry Reforming Of Benzene Used As A Surrogate Of Biomass Tar, Başar Çağlar, Deni̇z Üner

Turkish Journal of Chemistry

Tar build-up is one of the bottlenecks of biomass gasification process. Dry reforming of tar is an alternative solution if oxygen chemical potential on the catalyst surface is at sufficient levels. For this purpose, an oxygen donor perovskite, LaCoO3, was used as a catalyst for dry reforming of tar. To circumvent the complexity of the tar and its constituents, benzene molecule was chosen as a model compound. Dry reforming of benzene vapour on the LaCoO3 catalyst was investigated at temperatures of 600, 700, 800 °C, at the CO2/C6H6 ratios of 3, 6, 12 and at space velocities of 14000 and …

Identification Of Blood At Simulated Crime Scenes Using Silver Nanoparticles With Sers, Uğur Köroğlu, Necdet Sağlam, Uğur Tamer, Ramazan Akcan, İsmai̇l Hakki Boyaci, Eylül Evran

Turkish Journal of Chemistry

Analysis of substances and samples obtained from the crime scene are very important in solving forensic cases. In order to determine the variables involved in a crime and to expedite the investigation process, especially the rapid analysis of body fluids in a small quantity and within an environment containing diverse components is necessary. For this reason, it is of great importance to analyse biological fluids with rapid, non-chemical contamination, non-destructive, low-cost and accurate techniques. In recent years, with advancements in laser technology, spectroscopic methods have been introduced as an analytical technique in forensic medicine and chemical studies. This study focuses …