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Articles 121 - 150 of 1552
Full-Text Articles in Chemistry
Development Of Catalytic Membranes And Composites For Energy Storage Devices And Nonenzymatic Biosensors, Harish Singh
Development Of Catalytic Membranes And Composites For Energy Storage Devices And Nonenzymatic Biosensors, Harish Singh
Doctoral Dissertations
The excessive use of fossil fuels has led to their rapid depletion, causing an energy crisis and environmental issues. Consequently, there's a growing focus on sustainable energy conversion. Electrocatalysts are pivotal in this development, particularly for fuel cells and solar fuel generators, necessitating high-efficiency, cost-effective catalysts for large-scale adoption. Transition metal chalcogenides have emerged as promising electrocatalysts due to their high efficiency, electrochemical tunability, and abundant active sites. This work is divided in two parts. In Part A, we have investigated transition metal chalcogenide and few atom clusters FACs as electrocatalysts for oxygen evolution and reduction, highlighting their structure-property relationships …
Utility Of Immobilized Metal Salens As Electrocatalysts: Fuel Cells And Organic Electrosynthesis, Zachary A. Nguyen, Shelley D. Minteer
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 …
Ai Is A Viable Alternative To High Throughput Screening: A 318-Target Study, Izhar Wallach, Denzil Bernard, Kong Nguyen, Gregory Ho, Adrian Morrison, Adrian Stecula, Andreana Rosnik, Ann Marie O'Sullivan, Aram Davtyan, Ben Samudio, Bill Thomas, Brad Worley, Brittany Butler, Christian Laggner
Ai Is A Viable Alternative To High Throughput Screening: A 318-Target Study, Izhar Wallach, Denzil Bernard, Kong Nguyen, Gregory Ho, Adrian Morrison, Adrian Stecula, Andreana Rosnik, Ann Marie O'Sullivan, Aram Davtyan, Ben Samudio, Bill Thomas, Brad Worley, Brittany Butler, Christian Laggner
Chemistry Faculty Research & Creative Works
High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, …
Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk
Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Asphalt binder performance grades (PGs) are important metrics in designing pavements for effective transportation infrastructure. the PG system relies on the binder's stiffness and is determined through energy- and time-intensive physical testing. Physical properties, like stiffness, can also be determined by spin–lattice NMR relaxometry, a non-destructive chemical method. NMR relaxometry can quantify the molecular mobility of materials by determining relaxation times from exponential decays of excited nuclear magnetization. While relaxation times have been used to determine physical properties of materials, a quantitative relation to the PG grades of asphalt binder is yet to be established. in this study, T1 NMR …
Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo
Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO2, MoS2, and Al2O3) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment of 10 °C. Obtained results showed that thermal …
Elucidating The Significant Roles Of Root Exudates In Organic Pollutant Biotransformation Within The Rhizosphere, Michael O. Eze, Chinedu F. Amuji
Elucidating The Significant Roles Of Root Exudates In Organic Pollutant Biotransformation Within The Rhizosphere, Michael O. Eze, Chinedu F. Amuji
Chemistry Faculty Research & Creative Works
Biotransformation of organic pollutants is crucial for the dissipation of environmental pollutants. While the roles of microorganisms have been extensively studied, the significant contribution of various root exudates are still not very well understood. Through plant growth experiment, coupled with gas and liquid chromatography-mass spectrometry methods, this study examined the effect of the presence of M. sativa on microbial-associated biochemical transformation of petroleum hydrocarbons. The results of this study revealed that the concentration of exudates within the soil matrix is a function of proximity to root surfaces. Similarly, biodegradation was found to correlate with distance from roots, ranging from ≥ …
Experimental Evaluation Of A Recrosslinkable Co2-Resistant Micro-Sized Preformed Particle Gel For Co2 Sweep Efficiency Improvement In Reservoirs With Super-K Channels, Adel Alotibi, Tao Song, Ali Al Brahim, Baojun Bai, Thomas P. Schuman
Experimental Evaluation Of A Recrosslinkable Co2-Resistant Micro-Sized Preformed Particle Gel For Co2 Sweep Efficiency Improvement In Reservoirs With Super-K Channels, Adel Alotibi, Tao Song, Ali Al Brahim, Baojun Bai, Thomas P. Schuman
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
A recross linkable CO2-resistant branched preformed particle gel (CO2-BRPPG) was developed for controlling CO2 injection conformance, particularly in reservoirs with super-permeable channels. Previous work focused on a millimeter-sized CO2-BRPPG in open fractures, but its performance in high-permeability channels with pore throat networks remained unexplored. This study used a sand pack model to evaluate a micro-sized CO2-BRPPG under varying conditions of salinity, gel concentration, and pH. at ambient conditions, the equilibrium swelling ratio (ESR) of the gel reached 76 times its original size. This ratio decreased with increasing salinity but remained stable …
Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo
Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo
Chemical and Biochemical Engineering Faculty Research & Creative Works
This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-Based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO2, MoS2, and Al2O3) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment …
Multiphase Electrochemical Li-Ion Intercalation In Iron Selenite: Evidence Of Fe³⁺/⁴⁺ Redox And Single-Crystal-To-Single-Crystal Topochemical Transformation During Chemical Lithiation, Sutapa Bhattacharya, Aleksandr V. Chernatynskiy, Amitava Choudhury
Multiphase Electrochemical Li-Ion Intercalation In Iron Selenite: Evidence Of Fe³⁺/⁴⁺ Redox And Single-Crystal-To-Single-Crystal Topochemical Transformation During Chemical Lithiation, Sutapa Bhattacharya, Aleksandr V. Chernatynskiy, Amitava Choudhury
Physics Faculty Research & Creative Works
An iron selenite-based cathode compound, LiFe(SeO3)2, is synthesized via a simple hydrothermal route. The bulk purity of the compound is confirmed by powder X-ray diffraction (PXRD), Mössbauer spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The crystal structure determined from the single-crystal X-ray diffraction and Rietveld refinement of synchrotron PXRD data perfectly matches the previously reported structure in the I4̅2d space group. The crystal structure is built up of edge-sharing of FeO6 octahedra and LiO4 tetrahedra interconnected by SeO3 trigonal pyramidal units, forming a three-dimensional open framework network with channels through all three axes. …
Boosting The Power Performance Of Microbial Fuel Cells By Using Dual Nanomaterial-Modified Carbon Felt Electrodes, Krishna Thapa, Wenyan Liu, Yuwei Zhang, David J. Westenberg, Yishu Zhou, Risheng Wang
Boosting The Power Performance Of Microbial Fuel Cells By Using Dual Nanomaterial-Modified Carbon Felt Electrodes, Krishna Thapa, Wenyan Liu, Yuwei Zhang, David J. Westenberg, Yishu Zhou, Risheng Wang
Chemistry Faculty Research & Creative Works
Innovative design enhancements to microbial fuel cells (MFCs) are pivotal for improving their viability as renewable energy sources. This study introduces a dual approach to electrode modification, integrating polyaniline (PANI) and gold nanoparticles (AuNPs) on carbon felt (CF) anodes coupled with a unique cathode composed of DNA origami and chitosan. The synergistic effect of PANI and AuNPs significantly increases the hydrophilicity and conductivity of the anode, leading to a considerable surge in power density. Concurrently, the biocompatible DNA origami and chitosan-functionalized cathode facilitates efficient electron transfer without relying on conventional catalysts. Together, these modifications yield a 52.42% increase in the …
Microwave-Assisted Hydrothermal Synthesis Of Photocatalytic Truncated-Bipyramidal Tio2/Ti3cn Heterostructures Derived From Ti3cn Mxene, Muhammad Abiyyu Kenichi Purbayanto, Madhurya Chandel, Dominika Bury, Anna Wójcik, Dorota Moszczyńska, Anika Tabassum, Vadym Mochalin, Michael Naguib, Agnieszka Maria Jastrzębska
Microwave-Assisted Hydrothermal Synthesis Of Photocatalytic Truncated-Bipyramidal Tio2/Ti3cn Heterostructures Derived From Ti3cn Mxene, Muhammad Abiyyu Kenichi Purbayanto, Madhurya Chandel, Dominika Bury, Anna Wójcik, Dorota Moszczyńska, Anika Tabassum, Vadym Mochalin, Michael Naguib, Agnieszka Maria Jastrzębska
Chemistry Faculty Research & Creative Works
TiO2/MXene heterostructure has garnered significant interest as a photocatalyst due to its large surface area and efficient charge carrier separation at the interface. However, current synthesis methods produce TiO2 without clear crystal faceting and often require complicated postprocessing step, limiting its practical applications. We demonstrate a facile and controlled microwave-assisted hydrothermal synthesis for transforming multilayered Ti3CN MXene to a truncated-bipyramidal TiO2/Ti3CN heterostructure. The resulting TiO2 nanocrystals at the Ti3CN surface exhibited crystalline anatase truncated bipyramids, exposing {001} and {101} facets. We further tailored an indirect optical band gap …
Protocol For Evaluating Anion Exchange Membranes For Nonaqueous Redox Flow Batteries, Jessica L. Tami, Md Motiur R. Mazumder, Grace E. Cook, Shelley D. Minteer, Anne J. Mcneil
Protocol For Evaluating Anion Exchange Membranes For Nonaqueous Redox Flow Batteries, Jessica L. Tami, Md Motiur R. Mazumder, Grace E. Cook, Shelley D. Minteer, Anne J. Mcneil
Chemistry Faculty Research & Creative Works
Nonaqueous redox flow batteries often suffer from reduced battery lifetime and decreased coulombic efficiency due to crossover of the redox-active species through the membrane. One method to mitigate this undesired crossover is to judiciously choose a membrane based on several criteria: swelling and structural integrity, size and charge of redox active species, and ionic conductivity. Most research to date has focused on reducing crossover by synthesizing modified redox-active molecules and/or new membranes. However, no standard protocol exists to compare membranes and a comprehensive study comparing membranes has yet to be done. To address both these limitations, we evaluate herein 26 …
Development Of Malate Biosensor-Containing Hydrogels And Living Cell-Based Sensors, Nathan J. Ricks, Monica Brachi, Kevin Mcfadden, Rohit G. Jadhav, Shelley D. Minteer, Ming C. Hammond
Development Of Malate Biosensor-Containing Hydrogels And Living Cell-Based Sensors, Nathan J. Ricks, Monica Brachi, Kevin Mcfadden, Rohit G. Jadhav, Shelley D. Minteer, Ming C. Hammond
Chemistry Faculty Research & Creative Works
Malate is a key intermediate in the citric acid cycle, an enzymatic cascade that is central to cellular energy metabolism and that has been applied to make biofuel cells. To enable real-time sensing of malate levels, we have engineered a genetically encoded, protein-based fluorescent biosensor called Malon specifically responsive to malate by performing structure-based mutagenesis of the Cache-binding domain of the Citron GFP-based biosensor. Malon demonstrates high specificity and fluorescence activation in response to malate and has been applied to monitor enzymatic reactions in vitro. Furthermore, we successfully incorporated Malon into redox polymer hydrogels and bacterial cells, enabling analysis of …
Cobalt Molybdenum Telluride As An Efficient Trifunctional Electrocatalyst For Seawater Splitting, Rajarshi Kar, Amideddin Nouralishahi, Harish Singh, Manashi Nath
Cobalt Molybdenum Telluride As An Efficient Trifunctional Electrocatalyst For Seawater Splitting, Rajarshi Kar, Amideddin Nouralishahi, Harish Singh, Manashi Nath
Chemistry Faculty Research & Creative Works
A mixed-metal ternary chalcogenide, cobalt molybdenum telluride (CMT), has been identified as an efficient tri-functional electrocatalyst for seawater splitting, leading to enhanced oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and oxygen reduction reaction (ORR). The CMT was synthesized by a single step hydrothermal technique. Detailed electrochemical studies of the CMT-modified electrodes showed that CMT has a promising performance for OER in the simulated seawater solutions, exhibiting a small overpotential of 385 mV at 20 mA cm−2, and superior catalyst durability for prolonged period of continuous oxygen evolution. Interestingly, while gas chromatography analysis confirmed the evolution of oxygen …
C-H Amination Chemistry Mediated By Trinuclear Cu(I) Sites Supported By A Ligand Scaffold Featuring An Arene Platform And Tetramethylguanidinyl Residues, Meenakshi Sharma, Reece M. Fritz, Himanshu Bhatia, Joseph O. Adebanjo, Zhou Lu, Mohammad A. Omary, Thomas R. Cundari, Amitava Choudhury, Pericles Stavropoulos
C-H Amination Chemistry Mediated By Trinuclear Cu(I) Sites Supported By A Ligand Scaffold Featuring An Arene Platform And Tetramethylguanidinyl Residues, Meenakshi Sharma, Reece M. Fritz, Himanshu Bhatia, Joseph O. Adebanjo, Zhou Lu, Mohammad A. Omary, Thomas R. Cundari, Amitava Choudhury, Pericles Stavropoulos
Chemistry Faculty Research & Creative Works
Tripodal ligands that can encapsulate single or multiple metal sites in C3-symmetric geometric configurations constitute valuable targets for novel catalysts. Of particular interest in ligand development are efforts toward incorporating apical elements that exhibit little if any electron donicity, to enhance the electrophilic nature of a trans positioned active oxidant (e.g., metal-oxo, -nitrene). The tripodal ligand TMG3trphen-Arene has been synthesized, featuring an arene platform 1,3,5-substituted with phenylene arms possessing tetramethylguanidinyl (TMG) residues. Compound [(TMG3trphen-Arene) Cu3(μ-Cl)3] has been subsequently synthesized by extracting a Cu3(μ-Cl)3 cluster from anhydrous CuCl and shown to encapsulate a crown-shaped …
Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk
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
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 …
Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk
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 …
Kinetic Characterization And Identification Of Key Active Site Residues Of The L-Aspartate N-Hydroxylase, Cree, Sydney B. Johnson, Hannah Valentino, Pablo Sobrado
Kinetic Characterization And Identification Of Key Active Site Residues Of The L-Aspartate N-Hydroxylase, Cree, Sydney B. Johnson, Hannah Valentino, Pablo Sobrado
Chemistry Faculty Research & Creative Works
CreE is a flavin-dependent monooxygenase (FMO) that catalyzes three sequential nitrogen oxidation reactions of L-aspartate to produce nitrosuccinate, contributing to the biosynthesis of the antimicrobial and antiproliferative nautral product, cremeomycin. This compound contains a highly reactive diazo functional group for which the reaction of CreE is essential to its formation. Nitro and diazo functional groups can serve as potent electrophiles, important in some challenging nucleophilic addition reactions. Formation of these reactive groups positions CreE as a promising candidate for biomedical and synthetic applications. Here, we present the catalytic mechanism of CreE and the identification of active site residues critical to …
Kinetic Characterization And Identification Of Key Active Site Residues Of The L-Aspartate N-Hydroxylase, Cree, Sydney B. Johnson, Hannah Valentino, Pablo Sobrado
Kinetic Characterization And Identification Of Key Active Site Residues Of The L-Aspartate N-Hydroxylase, Cree, Sydney B. Johnson, Hannah Valentino, Pablo Sobrado
Chemistry Faculty Research & Creative Works
CreE is a flavin-dependent monooxygenase (FMO) that catalyzes three sequential nitrogen oxidation reactions of L-aspartate to produce nitrosuccinate, contributing to the biosynthesis of the antimicrobial and antiproliferative natural product, cremeomycin. This compound contains a highly reactive diazo functional group for which the reaction of CreE is essential to its formation. Nitro and diazo functional groups can serve as potent electrophiles, important in some challenging nucleophilic addition reactions. Formation of these reactive groups positions CreE as a promising candidate for biomedical and synthetic applications. Here, we present the catalytic mechanism of CreE and the identification of active site residues critical to …
Harnessing Redox Polymer Dynamics For Enhanced Glucose-Oxygen Coupling In Dual Biosensing And Therapeutic Applications, Wassim El Housseini, Egor Baiarashov, Rokas Gerulskis, Adam Milam, Shelley D. Minteer
Harnessing Redox Polymer Dynamics For Enhanced Glucose-Oxygen Coupling In Dual Biosensing And Therapeutic Applications, Wassim El Housseini, Egor Baiarashov, Rokas Gerulskis, Adam Milam, Shelley D. Minteer
Chemistry Faculty Research & Creative Works
The burgeoning field of continuous glucose monitoring (CGM) for diabetes management faces significant challenges, particularly in achieving precise and stable biosensor performance under changing environmental conditions such as varying glucose concentrations and O2 levels. To address this, we present a novel biosensor based on the electroless coupling of glucose oxidation catalyzed by flavin-dependent glucose dehydrogenase (FAD-GDH) and O2 reduction catalyzed by bilirubin oxidase (BOD) via a redox polymer, dimethylferrocene-modified linear poly(ethylenimine), FcMe2-LPEI. Initial cyclic voltammetry tests confirm the colocalization of both enzymatic reactions within the potential range of the polymer, indicating an effective electron shuttle mechanism. …
Interpenetrated Lattices Of Quaternary Chalcogenides Displaying Magnetic Frustration, High Na-Ion Conductivity, And Cation Redox In Na-Ion Batteries, Santhoshkumar Sundaramoorthy, Srikanth Balijapelly, Sudip Mohapatra, Sutapa Bhattacharya, Kartik Ghosh, Amitava Choudhury
Interpenetrated Lattices Of Quaternary Chalcogenides Displaying Magnetic Frustration, High Na-Ion Conductivity, And Cation Redox In Na-Ion Batteries, Santhoshkumar Sundaramoorthy, Srikanth Balijapelly, Sudip Mohapatra, Sutapa Bhattacharya, Kartik Ghosh, Amitava Choudhury
Chemistry Faculty Research & Creative Works
A series of quaternary selenides, NaxMGaSe4 (M = Mn, Fe, and mixed Zn/Fe), have been synthesized for the first time employing a high-temperature solid-state synthesis route through stochiometric or polychalcogenide flux reactions. Along with the selenides, a previously reported sulfide analogue, NaxFeGaS4, is also revisited with new findings. These compounds form an interpenetrated structure made up of a supertetrahedral unit. The electrochemical evaluations exhibit a reversible (de)intercalation of ∼0.6 and ∼0.45 Na-ions, respectively, from Na2.87FeGaS4 (1a) and Na2.5FeGaSe4 (2) involving Fe2+/Fe3+ redox when cycled between 1.5 and 2.5 …
Mechanism Of Nitrone Formation By A Flavin-Dependent Monooxygenase, Sydney B. Johnson, Hao Li, Hannah Valentino, Pablo Sobrado
Mechanism Of Nitrone Formation By A Flavin-Dependent Monooxygenase, Sydney B. Johnson, Hao Li, Hannah Valentino, Pablo Sobrado
Chemistry Faculty Research & Creative Works
OxaD is a flavin-dependent monooxygenase (FMO) responsible for catalyzing the oxidation of an indole nitrogen atom, resulting in the formation of a nitrone. Nitrones serve as versatile intermediates in complex syntheses, including challenging reactions like cycloadditions. Traditional organic synthesis methods often yield limited results and involve environmentally harmful chemicals. Therefore, the enzymatic synthesis of nitrone-containing compounds holds promise for more sustainable industrial processes. In this study, we explored the catalytic mechanism of OxaD using a combination of steady-state and rapid-reaction kinetics, site-directed mutagenesis, spectroscopy, and structural modeling. Our investigations showed that OxaD catalyzes two oxidations of the indole nitrogen of …
Visible-Light Photocatalytic C-H Amination Of Arenes Utilizing Acridine-Lewis Acid Complexes, Matthew R. Lasky, En Chih Liu, Matthew S. Remy, Melanie S. Sanford
Visible-Light Photocatalytic C-H Amination Of Arenes Utilizing Acridine-Lewis Acid Complexes, Matthew R. Lasky, En Chih Liu, Matthew S. Remy, Melanie S. Sanford
Chemistry Faculty Research & Creative Works
This report describes the development of a visible-light photocatalytic system for C(sp2)-H amination that leverages in situ-generated photocatalysts. We demonstrate that the combination of acridine derivatives and Lewis acids form potent photooxidants that promote the C-H amination of electronically diverse arenes upon irradiation with visible-light (440 nm). A first-generation photocatalyst composed of Sc (OTf)3 and acridine effects the C-H amination of substrates with oxidation potentials ≤ +2.5 V vs SCE with pyrazole, triazole, and pyridine nucleophiles. Furthermore, the simplicity and modularity of this system enable variation of both Lewis acid and acridine to tune reactivity. This enabled …
Advancing Simultaneous Extraction And Sequential Single-Particle Icp-Ms Analysis For Metallic Nanoparticle Mixtures In Plant Tissues, Lei Xu, Xingmao Ma, John Yang, Joel G. Burken, Paul Ki-Souk Nam, Honglan Shi, Hu Yang
Advancing Simultaneous Extraction And Sequential Single-Particle Icp-Ms Analysis For Metallic Nanoparticle Mixtures In Plant Tissues, Lei Xu, Xingmao Ma, John Yang, Joel G. Burken, Paul Ki-Souk Nam, Honglan Shi, Hu Yang
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Engineered Nanoparticles (ENPs) Have Been Increasingly Used in Agricultural Operations, leading to an Urgent Need for Robust Methods to Analyze Co-Occurring ENPs in Plant Tissues. in Response, This Study Advanced the Simultaneous Extraction of Coexisting Silver, Cerium Oxide, and Copper Oxide ENPs in Lettuce Shoots and Roots using Macerozyme R-10 and Analyzed Them by Single-Particle Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Additionally, the Standard Stock Suspensions of the ENPs Were Stabilized with Citrate, and the Long-Term Stability (Up to 5 Months) Was Examined for the First Time. the Method Performance Results Displayed Satisfactory Accuracies and Precisions and Achieved Low Particle Concentration …
Excellent Bifunctional Oxygen Evolution And Reduction Electrocatalysts (5a1/5)Co2o4 And Their Tunability, Xin Wang, Harish Singh, Manashi Nath, Kurt Lagemann, Katharine Page
Excellent Bifunctional Oxygen Evolution And Reduction Electrocatalysts (5a1/5)Co2o4 And Their Tunability, Xin Wang, Harish Singh, Manashi Nath, Kurt Lagemann, Katharine Page
Chemistry Faculty Research & Creative Works
Hastening the Progress of Rechargeable Metal-Air Batteries and Hydrogen Fuel Cells Necessitates the Advancement of Economically Feasible, Earth-Abundant, Inexpensive, and Efficient Electrocatalysts Facilitating Both the Oxygen Evolution Reaction (OER) and Oxygen Reduction Reaction (ORR). Herein, a Recently Reported Family of Nano (5A1/5) Co2O4 (A = Combinations of Transition Metals, Mg, Mn, Fe, Ni, Cu, and Zn) Compositionally Complex Oxides (CCOs) [Wang Et Al., Chemistry of Materials, 2023, 35 (17), 7283-7291.] Are Studied as Bifunctional OER and ORR Electrocatalysts. among the Different Low-Temperature Soft-Templating Samples, Those Subjected to 600 °C Post annealing Heat Treatment Exhibit Superior Performance in Alkaline Media. One …
Rotational Spectrum, Structure, And Quadrupole Coupling Of Cyclopropylchloromethyldifluorosilane, Alexander R. Davies, Abanob G. Hanna, Alma Lutas, Gamil A. Guirgis, Garry S. Grubbs
Rotational Spectrum, Structure, And Quadrupole Coupling Of Cyclopropylchloromethyldifluorosilane, Alexander R. Davies, Abanob G. Hanna, Alma Lutas, Gamil A. Guirgis, Garry S. Grubbs
Chemistry Faculty Research & Creative Works
Cyclopropylchloromethyldifluorosilane, C-C3H5SiF2CH2Cl, Has Been Synthesized, and its Rotational Spectrum Has Been Recorded by Chirped-Pulse Fourier Transform Microwave Spectroscopy. the Spectral Analysis of Several Isotopologues Indicates the Presence of Two Distinct Conformations in the Free-Jet Expansion, Which Are Interconvertible through a Rotation of the Chloromethyl Group. a Partial Substitution Structure is Presented for the Lower Energy Conformation and is Compared to the Equilibrium Structure Obtained from Quantum Chemical Calculations. Additionally, the Presence of the Chlorine Nucleus Leads to the Rotational Transitions Splitting into Multiple Hyperfine Components and Χaa, a Measure of the Electric Field Gradient Along the a Axis, is Unusually …
Vt-Nmr Analysis Of Rotation-Inversion Of N-(4-Hydroxybutyl)-N-(2,2,2-Trifluoroethyl) Tert-Butyl Carbamate: Utilizing The −Ch2cf3 Appendage As A Reporter On E/Z-Isomerization, Brian Jameson, Rainer Glaser
Vt-Nmr Analysis Of Rotation-Inversion Of N-(4-Hydroxybutyl)-N-(2,2,2-Trifluoroethyl) Tert-Butyl Carbamate: Utilizing The −Ch2cf3 Appendage As A Reporter On E/Z-Isomerization, Brian Jameson, Rainer Glaser
Chemistry Faculty Research & Creative Works
The rotational barrier about the CN carbamate bond of N-(4-hydroxybutyl)-N-(2,2,2-trifluoroethyl) tert-butyl carbamate 1 was determined by variable temperature (VT) 13C and 19F NMR spectroscopy. The −CH2CF3 appendage reports on rotational isomerism and allows for the observation of separate signals for the E- and Z-ensembles at low temperature. The activation barrier for E/Z-isomerization was quantified using Eyring-Polanyi theory which requires the measurements of the maximum difference in Larmor frequency Δνmax and the convergence temperature Tc. Both Δνmax and Tc were interpolated by analyzing sigmoidal functions fitted to data describing signal separation and the quality of the superposition of the E- and …
Li2mp2s6: Building-Block Approach To A Family Of 2d Non-Van Der Waals-Layered Materials And Their Water, Ammonia, And Ion Intercalation Properties, Santhoshkumar Sundaramoorthy, Nikolay Gerasimchuk, Kartik Ghosh, Steven P. Kelley, Amitava Choudhury
Li2mp2s6: Building-Block Approach To A Family Of 2d Non-Van Der Waals-Layered Materials And Their Water, Ammonia, And Ion Intercalation Properties, Santhoshkumar Sundaramoorthy, Nikolay Gerasimchuk, Kartik Ghosh, Steven P. Kelley, Amitava Choudhury
Chemistry Faculty Research & Creative Works
A Series of Non-Van Der Waals 2D Quaternary Thiophosphates with Nominal Composition, Li2MP2S6 (M = V, Mn, Fe, Co, Ni, and Zn), Has Been Successfully Synthesized through Solid-State Metathesis Reactions by a Building Block Approach as Well as Starting with a Stoichiometric Combination of Elements. Li4-NxMxn+P2S6 (M = V, Fe, Ni, Co, and Zn; X = 0.5-1, N = 2 or 3) Crystallize in the P3̅1m Space Group, While Li2MnP2S6 Crystallizes in R3̅. All the Compounds Form a 2D Layered Structure through Edge Sharing MS6 Octahedra and P2S6 Units with Li Atoms Occupying the Interlayer Spaces. X-Ray Diffraction and Thermogravimetric …
Li2mp2s6: Building-Block Approach To A Family Of 2d Non-Van Der Waals-Layered Materials And Their Water, Ammonia, And Ion Intercalation Properties, Santhoshkumar Sundaramoorthy, Nikolay Gerasimchuk, Kartik Ghosh, Steven P. Kelley, Amitava Choudhury
Li2mp2s6: Building-Block Approach To A Family Of 2d Non-Van Der Waals-Layered Materials And Their Water, Ammonia, And Ion Intercalation Properties, Santhoshkumar Sundaramoorthy, Nikolay Gerasimchuk, Kartik Ghosh, Steven P. Kelley, Amitava Choudhury
Chemistry Faculty Research & Creative Works
A series of non-van der Waals 2D quaternary thiophosphates with nominal composition, Li2MP2S6 (M = V, Mn, Fe, Co, Ni, and Zn), has been successfully synthesized through solid-state metathesis reactions by a building block approach as well as starting with a stoichiometric combination of elements. Li4-nxMxn+P2S6 (M = V, Fe, Ni, Co, and Zn; x = 0.5-1, n = 2 or 3) crystallize in the P3̅1m space group, while Li2MnP2S6 crystallizes in R3̅. All the compounds form a 2D layered structure through edge sharing MS6 octahedra and P2S …