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Articles 841 - 870 of 33135

Full-Text Articles in Chemistry

Superhydrophilic Porous Coooh Nano-Architecture With Abundant Oxygen Vacancies For Enhanced Urea Electrooxidation At Ampere-Level Current Densities, Wen-Jing Lv, Xiao-Man Tang, Xue-Tong Wang, Wen-Cai Liu, Jian-Wen Zhu, Guo-Jing Wang, Yuan-Zhi Zhu Aug 2025

Superhydrophilic Porous Coooh Nano-Architecture With Abundant Oxygen Vacancies For Enhanced Urea Electrooxidation At Ampere-Level Current Densities, Wen-Jing Lv, Xiao-Man Tang, Xue-Tong Wang, Wen-Cai Liu, Jian-Wen Zhu, Guo-Jing Wang, Yuan-Zhi Zhu

Journal of Electrochemistry

The conversion of urea-containing wastewater into clean hydrogen energy has gained increasing attention. However, challenges remain, particularly with sluggish catalytic kinetics and limited long-term stability of urea oxidation reaction (UOR). Herein, we report the loosely porous CoOOH nano-architecture (CoOOH LPNAs) with hydrophilic surface and abundant oxygen vacancies (Ov) on carbon fiber paper (CFP) by electrochemical reconstruction of the CoP nanoneedles precursor. The resulting three-dimensional electrode exhibited an impressively low potential of 1.38 V at 1000 mA·cm−2 and excellent durability for UOR. Furthermore, when tested in an anion exchange membrane (AEM) electrolyzer, it required only 1.53 V at …


Structure Regulation Engineering For Biomass-Derived Carbon Anodes Enabling High-Rate Dual-Ion Batteries, Rui Zhou, Rui Liu, Yun-Nuo Li, Si-Jie Jiang, Tian-Tian Jing, Yan-Song Xu, Fei-Fei Cao Aug 2025

Structure Regulation Engineering For Biomass-Derived Carbon Anodes Enabling High-Rate Dual-Ion Batteries, Rui Zhou, Rui Liu, Yun-Nuo Li, Si-Jie Jiang, Tian-Tian Jing, Yan-Song Xu, Fei-Fei Cao

Journal of Electrochemistry

Dual-ion batteries (DIBs) usually use carbon-based materials as electrodes, showing advantages in high operating voltage, potential low cost, and environmental friendliness. Different from conventional “rocking chair” type secondary batteries, DIBs perform a unique working mechanism, which employ both cation and anion taking part in capacity contribution at an anode and a cathode, respectively, during electrochemical reactions. Graphite has been identified as a suitable cathode material for anion intercalation at high voltages (> 4.8 V) with fast reaction kinetics. However, the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+ …


Design And Optimization Of Anode Catalysts For Direct Ethanol Fuel Cells: Advances And Challenges In C-C Bond Activation And Selective Modulation Of The C1 Pathway, Kai-Chi Qin, Meng-Tian Huo, Yu Liang, Si-Yuan Zhu, Zi-Hao Xing, Jin-Fa Chang Aug 2025

Design And Optimization Of Anode Catalysts For Direct Ethanol Fuel Cells: Advances And Challenges In C-C Bond Activation And Selective Modulation Of The C1 Pathway, Kai-Chi Qin, Meng-Tian Huo, Yu Liang, Si-Yuan Zhu, Zi-Hao Xing, Jin-Fa Chang

Journal of Electrochemistry

Direct ethanol fuel cells (DEFCs) are a promising alternative to conventional energy sources, offering high energy density, environmental sustainability, and operational safety. Compared to methanol fuel cells, DEFCs exhibit lower toxicity and a more mature preparation process. Unlike hydrogen fuel cells, DEFCs provide superior storage and transport feasibility, as well as cost-effectiveness, significantly enhancing their commercial viability. However, the stable C–C bond in ethanol creates a high activation energy barrier, often resulting in incomplete electrooxidation. Current commercial platinum (Pt)- and palladium (Pd)-based catalysts demonstrate low C–C bond cleavage efficiency (


Effect Of Saccharin On Crystallization Behavior Of Electroless Cobalt Plating, Yu-Xin Luo, Jing-Jing Wang, Lu Wang, Zi-Yi Yan, Yi Ma, Xin Bo, Jing-Shuang Dang, Zeng-Lin Wang Aug 2025

Effect Of Saccharin On Crystallization Behavior Of Electroless Cobalt Plating, Yu-Xin Luo, Jing-Jing Wang, Lu Wang, Zi-Yi Yan, Yi Ma, Xin Bo, Jing-Shuang Dang, Zeng-Lin Wang

Journal of Electrochemistry

In the process of electroless cobalt plating, the saccharin additive can significantly change the surface morphology, texture orientation, and conductivity of the cobalt coating layer. When the amount of saccharin was 3 mg·L–1, the cobalt coating transformed from disordered large grains to a honeycomb structure, with a preferred orientation of (002) facet on hexagonal close-packed (HCP) cobalt crystals. The resistivity of the cobalt film decreased to 14.4 μΩ·cm, and further decreased to 10.7 μΩ·cm after the annealing treatment. When the concentration of saccharin was increased, the grain size was gradually refined and a “stone forest” structure was observed, …


Effects Of Ambient Temperature On Nox Emissions From Heavy-Duty Diesel Vehicles Measured In Utah, Amber L. Gurecki Allen, Darrell B. Sonntag, Gary A. Bishop Aug 2025

Effects Of Ambient Temperature On Nox Emissions From Heavy-Duty Diesel Vehicles Measured In Utah, Amber L. Gurecki Allen, Darrell B. Sonntag, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

This study investigates the effects of ambient temperature on NOx (NO + NO2) emissions from model year 2011 and later heavy-duty (HD) diesel vehicles. Emission measurements were collected in Perry, Utah, using the Fuel Efficiency Automobile Test (FEAT) remote sensing device. Data were limited to model year 2011 and later to focus on vehicles likely equipped with selective catalytic reduction (SCR) systems, which control tailpipe NOx emissions and are shown to be temperature sensitive. HD diesel vehicles measured in the winter of 2020 had consistently higher NOx emissions than those measured in the summer of 2023, most significantly for vehicles …


Anionic Azo Dyes: Wastewater Pollutants As Functionalizing Agents For Porous Polycarbonate Membranes Aiding In Water Decolorization, Alan Jarrett Messinger, Isabella S. Mays, Brennon Craigo, Jeffrey Joering, Sean P. Mcbride Aug 2025

Anionic Azo Dyes: Wastewater Pollutants As Functionalizing Agents For Porous Polycarbonate Membranes Aiding In Water Decolorization, Alan Jarrett Messinger, Isabella S. Mays, Brennon Craigo, Jeffrey Joering, Sean P. Mcbride

Physics Faculty Research

Efficient water decolorization techniques are vital for ensuring fresh water for future generations. Azo dyes are used heavily in the textile industry and are a challenge to remove from industrial wastewater. This research expands on recent innovative work where anionic azo dyes themselves were used to functionalize track-etched porous polycarbonate filtration membranes with decolorized water obtained as a byproduct. The objective of this research is to determine whether the observed dye rejection is dependent on the magnitude of the intrinsic charge of the dye molecule or on its structure, using two selectively chosen anionic azo dye series during functionalization. The …


Effect Of Chalcogen-Phosphorus Substituents On Enediynes Undergoing The Bergman Cyclization, Marcos Hendler, Travis Greene, Dominic A. Siriani, Carol A. Parish Aug 2025

Effect Of Chalcogen-Phosphorus Substituents On Enediynes Undergoing The Bergman Cyclization, Marcos Hendler, Travis Greene, Dominic A. Siriani, Carol A. Parish

Chemistry Faculty Publications

We have theoretically characterized electrocyclizations of chalcogen-phosphorus-containing enediynes. We performed quantum calculations at the BS-(U)­CCSD/cc-pVDZ level to analyze the geometries and energetics of two different cyclization pathways, each consisting of the first three chalcogens (oxygen, sulfur, and selenium). The first pathway involved the cyclization of the chalcogen-phosphorus substituents followed by Bergman cyclization, while the second pathway proceeded via Bergman cyclization followed by chalcogen-phosphorus cyclization. To more accurately understand the energies of the diradicals involved in each pathway, we also performed spin-flip characterizations using UHF reference wave functions and the spin-flip formulation of the equation-of-motion coupled cluster theory with singles and …


Rising Costs Of Higher Education In United States And Student Debt, Mona Muzammil, Muzammil Arshad, Washain Muzammil Aug 2025

Rising Costs Of Higher Education In United States And Student Debt, Mona Muzammil, Muzammil Arshad, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

100 years ago, college tuition at prestigious Ivy League colleges such as Harvard and Brown was about $130 per year. Even when adjusted for inflation, today's cost of higher education has increased dramatically to the point where a college education is shifting further out of reach for many Americans. This book explains the essential concepts in the debate regarding the staggering costs of higher education, supplying ten original essays by higher education policy experts, a lively historical narrative that provides context to current issues, and systematic guides to find additional sources of information on the subject.

Written from a historian's …


Flash Communication: Visible-Light-Driven, Cobalt-Mediated Selective C–H Arylation Of 2,2′-Bipyridine, Xi Chen, Eric R. Allen, Mckenzie L. Stack, Zachary M. Garozzo, Dian Wang Aug 2025

Flash Communication: Visible-Light-Driven, Cobalt-Mediated Selective C–H Arylation Of 2,2′-Bipyridine, Xi Chen, Eric R. Allen, Mckenzie L. Stack, Zachary M. Garozzo, Dian Wang

Chemistry Faculty Research and Publications

Herein, we report a visible-light-driven, cobalt-mediated, highly selective C–H arylation method to afford aryl-2,2′-bipyridine, a widely used class of ancillary ligands in transition metal catalysis. This arylation reaction exhibits good-to-excellent C6 selectivity for a variety of aryl groups, allowing for isolation of the 6-isomer in its pure form. Mechanistic studies provided evidence for the generation of an aryl radical by the joint action of [Co(bpy)3] species and visible light, enabling arylation under mild conditions. Compared to previous work, this method employs cost-effective reagents and provides one-step, direct access from 2,2′-bipyridine to a broad range of electronically varied 6-aryl-2,2′-bipyridine …


Simulating Chemiluminescence Spectra Of Oh Radical Using Quantum Dynamical Simulations, Triet M. Cao Aug 2025

Simulating Chemiluminescence Spectra Of Oh Radical Using Quantum Dynamical Simulations, Triet M. Cao

Research from the Berry Summer Thesis Institute, 2025

Chemiluminescence is a phenomenon of light emission that occurs when molecules transition from an excited state to the ground state. This phenomenon is widely utilized in applications ranging from quantifying product yields in chemical reactions to biological imaging and atmospheric chemistry studies. It has also been used in many crucial applications in the scarce conditions of heat and electricity, such as light sources for astronomy discovery or deep-sea diving. A notable example of such reactions is combustion, where highly reactive hydroxyl radicals (OH) are products. These radicals exhibit a chemiluminescence spectrum because of the interaction between their ground state and …


Characterization Of L-Band Resonators And Relaxation Times Of Soₓ- Radicals At X-Band, Georgina Naa Odey Amassah Aug 2025

Characterization Of L-Band Resonators And Relaxation Times Of Soₓ- Radicals At X-Band, Georgina Naa Odey Amassah

Electronic Theses and Dissertations

Electron Paramagnetic Resonance (EPR) analysis requires resonators optimized for specific experimental challenges. Volume resonators enclose samples, while surface coil resonators allow imaging of larger subjects. For in vivo studies, L-band frequencies are commonly used because they offer a good balance between signal-to-noise ratio (S/N) and the ability to penetrate tissue. Rapid Scan (RS) EPR at L-band frequencies was chosen for my studies of resonators because of this balance but presents a challenge for sensitivity.

The spatial position dependence of signal intensity was evaluated for selected paramagnetic samples using 10 mm and 30 mm surface coils. The 10 mm coil, with …


Behavioral Neuroscience Of Drug Addiction And Mental Disorder, Mona Muzammil, Muzammil Arshad, Washain Muzammil Aug 2025

Behavioral Neuroscience Of Drug Addiction And Mental Disorder, Mona Muzammil, Muzammil Arshad, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

This book explores the molecular, cellular, and neurocircuitry systems in the brain that are responsible for drug addiction. Common neurobiological elements are emphasized that provide novel insights into how the brain mediates the acute rewarding effects of drugs of abuse and how it changes during the transition from initial drug use to compulsive drug use and addiction. The book provides a detailed overview of the pathophysiology of the disease. The information provided will be useful for neuroscientists in the field of addiction, drug abuse treatment providers, and undergraduate and postgraduate students who are interested in learning the diverse effects of …


Co-Catalyst Modified Mn-Doped Semiconductor Hybrid Nanostructures For Enhanced Photocatalysis, Walker John Macswain Aug 2025

Co-Catalyst Modified Mn-Doped Semiconductor Hybrid Nanostructures For Enhanced Photocatalysis, Walker John Macswain

Dissertations - ALL

Semiconductor nanocrystals (NCs) are sought after for their applications in photocatalysis and photovoltaics and due to their impressive optical and electronic properties. In photocatalysis, an important green energy transformation is sunlight utilization to produce hydrogen gas via photocatalytic water splitting. However, the photocatalytic performance of pristine semiconductors is low due to their inherent fast charge recombination. The use of co-catalysts with semiconductor NCs leads to enhanced photocatalytic product generation; noble metal co-catalysts, such as Pt, Au, Ag, and Cu and noble-metal-free metal hydroxide co-catalysts on either chalcogenide CdS or perovskite CsPbX3 (X = Cl, Br) semiconductors were synthesized to study …


Designing A Data Collection And Visualization Toolkit For Scalable Tensor Algebra In Quantum Chemistry Applications, Epiya J. Ebiapia Aug 2025

Designing A Data Collection And Visualization Toolkit For Scalable Tensor Algebra In Quantum Chemistry Applications, Epiya J. Ebiapia

LSU Master's Theses

Large-scale quantum chemistry computations, such as those executed with the Tensor Algebra for Many-body Methods (TAMM) framework, require careful configuration of runtime parameters to achieve high performance and cost efficiency in high-performance computing (HPC) and cloud environments. Without effective performance analysis tools, researchers risk inefficient use of computational resources, leading to longer runtimes and higher costs.

To address this challenge, this thesis presents the design and implementation of a performance profiling and visualization toolkit for TAMM, developed as part of the DOE TEC4 project in collaboration with Pacific Northwest National Laboratory, Microsoft, and Louisiana State University. The toolkit collects detailed …


Oxidation Resistance And Osmotic Energy Harvesting Applications Of Reduced Graphene Oxide Forward Osmosis Membranes, Michael Appiah-Kubi Aug 2025

Oxidation Resistance And Osmotic Energy Harvesting Applications Of Reduced Graphene Oxide Forward Osmosis Membranes, Michael Appiah-Kubi

Theses and Dissertations

Reduced graphene oxide (RGO) forward osmosis (FO) membranes have emerged as promising candidates for efficient wastewater management and osmotic energy harvesting, due to their enhanced chemical stability and superior FO performance for low-energy waste brine treatments, such as volume reduction of oxidative chromium brine for cost-effective disposal. This dissertation first examines the oxidation resistance of RGO forward osmosis membranes against chromate Cr (VI). Our findings reveal that both the water flux and the reverse salt flux of RGO membranes are suppressed, accompanying an enhanced reverse flux selectivity after exposure to an acidic medium of Cr (VI) (pH 2.0-7.0). Meanwhile, the …


Milkfish (Chanos Chanos) Bones As A Biosorbent For Mercury (Ii) Contamination In Water, Seth Uriel K. Neri, Ethan Kyle Mangao, Christian Kevin F. Redoblado, Anthony Cesar Y. Ponce, Roby Boy P. Riego, Jupiter O. Yap Aug 2025

Milkfish (Chanos Chanos) Bones As A Biosorbent For Mercury (Ii) Contamination In Water, Seth Uriel K. Neri, Ethan Kyle Mangao, Christian Kevin F. Redoblado, Anthony Cesar Y. Ponce, Roby Boy P. Riego, Jupiter O. Yap

Sinaya: A Philippine Journal for Senior High School Teachers and Students

Heavy metals, such as mercury contamination in water sources are a major environmental and public health issue in many countries. Traditional methods for removing heavy metals from water are effective but often costly and unsustainable and may produce secondary waste. Recent trends favor more sustainable alternatives, such as biosorbents in treating water with heavy metals. Milkfish (Chanos chanos), a common fish in the Philippines, contains hydroxyapatite in the bones that can bind with heavy metals through physical and chemical adsorption mechanisms. This study aims to evaluate the mercury (II) reduction capacity of biosorbent derived from milkfish bones in water, specifically …


Time-Resolved Crystallographic Analysis Of The Mechanism Of Formation Of The Mof Hkust-1, Cody Webb Jr Aug 2025

Time-Resolved Crystallographic Analysis Of The Mechanism Of Formation Of The Mof Hkust-1, Cody Webb Jr

Dissertations - ALL

Metal-organic frameworks (MOFs) are a class of inorganic porous coordination compounds of interest for technically relevant applications including gas storage & sequestration, catalysis, and drug delivery (Chapter 2). The last decade has seen significant development in this field of coordination chemistry, and an extensive array of MOFs have been reported despite the lack of a comprehensive scheme for how these materials form. The development of novel MOFs is not a trivial task, as the synthesis of target MOFs is notably unpredictable, and experiments require extensive trial-and-error reactions with systematic manipulation of the synthetic variables. Ideally, a toolbox method based on …


Revealing The Catalytic Mechanism Of The Fe(Ii)/2-Oxoglutarate-Dependent Human Epigenetic Modifying Enzyme Alkbh5, Fathima Hameed Cherilakkudy, Midhun George Thomas, Ann Varghese, Sodiq Waheed, Anandhu Krishnan, Vincenzo Venditti, Christopher J. Schofield, Deyu Li, Christo Christov, Tatyana Karabencheva-Christova Aug 2025

Revealing The Catalytic Mechanism Of The Fe(Ii)/2-Oxoglutarate-Dependent Human Epigenetic Modifying Enzyme Alkbh5, Fathima Hameed Cherilakkudy, Midhun George Thomas, Ann Varghese, Sodiq Waheed, Anandhu Krishnan, Vincenzo Venditti, Christopher J. Schofield, Deyu Li, Christo Christov, Tatyana Karabencheva-Christova

Michigan Tech Publications

ALKBH5 is one of only two known human non-heme Fe(II)/2-oxoglutarate-dependent oxygenases that catalyze the demethylation of N6-methyladenine (m6A) in single-stranded mRNA, underscoring its role in diverse cancers. Unlike its homolog, the fat mass and obesity-associated protein (FTO), which oxidizes m6A to a stable N6-hydroxymethyladenine (hm6A) intermediate, ALKBH5 demethylates m6A, yielding adenine and formaldehyde as products. Here, we integrate molecular dynamics simulations and quantum mechanics/molecular mechanics methods to elucidate ALKBH5’s complete catalytic mechanism. Two post-hydroxylation pathways were evaluated: a proton transfer pathway and a Schiff base formation pathway, with …


Tmco1 As An Endoplasmic Reticulum Calcium Load-Activated Channel: Mechanisms And Disease Implications, Jingbo Wang, Panpan Zhu, Zhuohang Li, Xiaohui Su, Mingzhu Qi, Aimin Zhou, Xiangying Kong Aug 2025

Tmco1 As An Endoplasmic Reticulum Calcium Load-Activated Channel: Mechanisms And Disease Implications, Jingbo Wang, Panpan Zhu, Zhuohang Li, Xiaohui Su, Mingzhu Qi, Aimin Zhou, Xiangying Kong

Chemistry Faculty Publications

Calcium ions (Ca2+) play a vital role in many biological processes. Transmembrane and coiled-coil domain 1 (TMCO1) has been characterized as an endoplasmic reticulum (ER) transmembrane protein in recent years. It keeps the cytoplasm and ER's Ca2+ homeostasis stable by acting as a novel calcium channel. Studies from different laboratories have revealed that the mutation or deficiency of TMCO1 is closely correlated with several diseases, including cerebro-facio-thoracic dysplasia (CFTD), glaucoma, premature ovarian failure (POF), osteoporosis, and cancer. Here, we review the characteristics of TMCO1 and its involvement in related diseases, which may provide useful information for developing therapeutic strategies for …


Mechanistic Study Of The Evan's Anti-Aldol Reaction, Aidan Hau Aug 2025

Mechanistic Study Of The Evan's Anti-Aldol Reaction, Aidan Hau

Summer Research Showcase

The Evans Aldol reaction can make a syn product with a boron, lithium, or titanium catalyst. The anti product is catalyzed by magnesium instead. Our goal is to understand the mechanism behind the formation of the anti product. We used WebMO to model what the lowest energy reaction pathways would be with a magnesium catalyst. We played with coordination to the magnesium and electron geometry to see if that would generate a low energy pathway that is likely to occur. We can use our information gathered to help determine the anti mechanism.


Determination Of The Reaction Mechanism For The Tautomerization Of Tröger’S Base, Cole Schliep Aug 2025

Determination Of The Reaction Mechanism For The Tautomerization Of Tröger’S Base, Cole Schliep

Summer Research Showcase

Tröger’s base is a unique V-shaped, bicyclic, chiral molecule that has the flexibility to have derivatives added to its carbon backbone. This allows for Tröger’s base to be used in many material applications. This research focuses on the addition of a carbamoyl group(-CONEt2) to Tröger’s base that can form either an endo- or exo-isomeric form. The exo-derivative of Tröger’s base is shown to be the more stable species. Recent work has shown that the endo-derivative can be selectively produced by sequential proton transfer under highly-basic, cold conditions, through deprotonation followed by a protic quench. Prior research has predicted that this …


Synthesis And Characterization Of Near-Infrared Fluorescent Dye Cy7-2 For Targeted Cancer Imaging, Eleanor Yerkin Aug 2025

Synthesis And Characterization Of Near-Infrared Fluorescent Dye Cy7-2 For Targeted Cancer Imaging, Eleanor Yerkin

Summer Research Showcase

The growing demand for real-time, precise, cancer diagnostics and treatment has driven the development of targeted near-infrared (NIR) fluorescent biosensors. Traditional visible-range fluorophores, such as Boron-dipyrromethene (BODIPY) dyes are well-known for their high quantum yields, photostability, biocompatibility, and sharp absorption and emission peaks, making them widely used in fluorescence imaging (Nisar and Sui). However, Cyanine dyes offer some advantages over visible-range dyes, such as deeper tissue penetration due to their near-infrared (NIR) absorption and emission, significantly reduced background autofluorescence, and improved signal-to- noise ratios in vivo (Zhang et al.). This project explores the synthesis and characterization of the NIR fluorescent …


Efficient Decontamination Of Organophosphate-Based Pesticides And Nerve Agent Simulants Mediated By N-Containing Nucleophiles, Emmanuel Kingsley Darkwah, Puspa Aryal, Saidulu Todeti, Jared Kenik, Samuel Insall, V. Prakash Reddy, Chariklia Sotiriou-Leventis Aug 2025

Efficient Decontamination Of Organophosphate-Based Pesticides And Nerve Agent Simulants Mediated By N-Containing Nucleophiles, Emmanuel Kingsley Darkwah, Puspa Aryal, Saidulu Todeti, Jared Kenik, Samuel Insall, V. Prakash Reddy, Chariklia Sotiriou-Leventis

Chemistry Faculty Research & Creative Works

There is a growing interest in developing safer and more effective decontaminating agents for organophosphate-based pesticides and nerve agents. In this study, we present an effective method for the nonaqueous decontamination of these compounds using small-molecule-based decontaminating agents under ambient conditions. Our approach utilizes aryl and heteroaryl carboxaldehyde hydrazones and hydrazides to effectively hydrolyze nerve agent simulants into their nontoxic degradation products. The effectiveness of this method was evaluated using a range of nerve agent simulants, including dimethyl 4-nitrophenyl phosphate (DMNP), dimethyl methyl phosphonate (DMMP), and triphenyl phosphate (TPhP). In the presence of the heteroaryl hydrazone, the rate of hydrolysis …


New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith Aug 2025

New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

As precipitation infiltrates into soils, it can recharge them, displace previously stored waters, or bypass already-filled pores. Using 3,697 δ2H and δ18O measurements of water collected nearly monthly over >3 years in 47 forest plots across Switzerland, we present a systematic investigation of the controls on mobile soil water transport. We quantified the lags and damping of water as it percolates downward using young water fraction analysis (Fyw), and the fractions of soil water composed by precipitation that fell within the previous month (new water fractions, Fnew). The Fnew of water sampled in surface soils ranged …


Instability Of The Octahedral Symmetry In Si8o12h8 And Ge8o12h8: A Consequence Of The Pseudo-Jahn–Teller Effect, Jules Tshishimbi Muya, Arnout Ceulemans, Carol A. Parish Aug 2025

Instability Of The Octahedral Symmetry In Si8o12h8 And Ge8o12h8: A Consequence Of The Pseudo-Jahn–Teller Effect, Jules Tshishimbi Muya, Arnout Ceulemans, Carol A. Parish

Chemistry Faculty Publications

The symmetry breaking in octahedral silsesquioxane and its germanium analogues (Si8O12H8 and Ge8O12H8) has been investigated using the M06-2X/6-31++G(3df, 3pd) method and group theory. Both structures undergo  symmetry breaking, characterized by pseudo-Jahn−Teller stabilization energies of 0.22 kcal/mol for Si-POSS and 9.82 kcal/mol for Ge-POSS. Under the influence of the pseudo-Jahn–Teller effect, the distortion vector involves the vibrational a2g mode with imaginary frequency. The distortion forces in Oh-POSS are predominantly localized on the oxygen atoms and driven by the coupling between the lowest unoccupied molecular orbital (a1g) and the highest occupied molecular orbital (a2g). The symmetry breaking is attributed to a …


Optimizing Polyamide Thin-Film Composite Desalination Membranes: Simple And Performance-Effective Modification By Zwitterionic Monohydroxyl Monomer, Selda Erkoç İlter Aug 2025

Optimizing Polyamide Thin-Film Composite Desalination Membranes: Simple And Performance-Effective Modification By Zwitterionic Monohydroxyl Monomer, Selda Erkoç İlter

Turkish Journal of Chemistry

A synthesized zwitterionic monohydroxyl monomer (ZHM) was used as an additive to incorporate zwitterionic sulfobetaine groups into the polyamide (PA) active layers of thin-film composite membranes. Incorporation of ZHM into the PA active layers was achieved through interfacial polymerization, involving the introduction of ZHM and m-phenylenediamine (MPD) into the aqueous phase, and the addition of trimesoyl chloride (TMC) to the hexane phase. The surfaces of the resulting reverse osmosis (RO) membranes were subjected to characterization through water contact angle (WCA) and field emission scanning electron microscopy (FESEM) analyses. The successful incorporation of ZHM into the active PA layers was confirmed …


Comprehensive Study Of Imidazole-Based Hydrazones: From Design, Synthesis, And Characterization To In Vitro And In Silico Antiproliferative Activity Analysis, Ömer Di̇lek Aug 2025

Comprehensive Study Of Imidazole-Based Hydrazones: From Design, Synthesis, And Characterization To In Vitro And In Silico Antiproliferative Activity Analysis, Ömer Di̇lek

Turkish Journal of Chemistry

The aim of this study was to synthesize novel imidazole-cored hydrazones and investigate their cytotoxic activities against human breast and lung cancer cell lines using in vitro and in silico techniques. For this purpose, 5 novel compounds (6 and 7a–7d) were synthesized. The structures of the synthesized compounds were confirmed using spectroscopic methods. The cytotoxic effects were evaluated against human lung (A549) and breast (MCF-7) cancer cell lines using the MTT assay. All synthesized compounds had higher cytotoxic activity against MCF-7 cells (IC50 < 9.262 μM) than the control drug cisplatin. However, their cytotoxic activity against A549 cells (IC50 > 2.605 μM) was lower than that of cisplatin. Except for compound 7d in the A549 cell line, …


A Decision Model For Enhancing Reaction Yield: Pd(Ii) And Pt(Ii) Metal Insertion To Free Porphyrin, Özay Özaydin, Emel Önal Aug 2025

A Decision Model For Enhancing Reaction Yield: Pd(Ii) And Pt(Ii) Metal Insertion To Free Porphyrin, Özay Özaydin, Emel Önal

Turkish Journal of Chemistry

Chemical synthesis experiments are crucial for developing new materials, yet their inherent complexity and variability often lead to suboptimal results, causing significant resource and time wastage. This study proposes a novel decision support model to enhance the success rate of macromolecule synthesis experiments for sensor applications. The model leverages principles of experimental design and decision-making. We identified synthesis alternatives through a literature review and expert consultations, narrowing it down to 6 alternatives for metal salts, 3 for reactant mole ratios, 5 for organic solvents, 3 for reaction temperatures, and 4 for reaction times. Considering the time and cost constraints, this …


Synthesis, Characterization, And Drug Release Properties Of Enzyme-Responsive Oxamide-Bridged Mesoporous Organosilica Nanoparticles, Yaşar Gök, Hali̇l Zeki̇ Gök, Osman Tayyar Arli, Tuğçe Türkaslan Aug 2025

Synthesis, Characterization, And Drug Release Properties Of Enzyme-Responsive Oxamide-Bridged Mesoporous Organosilica Nanoparticles, Yaşar Gök, Hali̇l Zeki̇ Gök, Osman Tayyar Arli, Tuğçe Türkaslan

Turkish Journal of Chemistry

In this study, we report a novel enzyme-responsive mesoporous organosilica nanocarrier (MON) and its drug delivery properties in the presence of the trypsin enzyme. The mesoporous organosilica nanocarrier was synthesized by using the oxamide bridged bissilyl compound (2) and 1,4-bis(triethoxysilyl)benzene (BTSB). To compare the enzyme responsiveness of MON, the reference periodic mesoporous organosilica (PMO) nanocarrier was also synthesized using BTSB only. The structural determinations of the synthesized organic compounds were carried out by 1H, 13C-NMR, FT-IR, and MS, while FT-IR, XRD, SEM, EDS, transmission electron microscopy (TEM), TGA, and N2 sorption analyses were used for the characterization of MON and …


Selective Extraction Of Scandium From Other Rare Earth Elements Using A Hydrophobic Protic Ionic Liquid Composed Of Decanoic Acid And Toa, Pius Dore Ola, Reo Nishioka, Yoshiro Tahara, Michiaki Matsumoto Aug 2025

Selective Extraction Of Scandium From Other Rare Earth Elements Using A Hydrophobic Protic Ionic Liquid Composed Of Decanoic Acid And Toa, Pius Dore Ola, Reo Nishioka, Yoshiro Tahara, Michiaki Matsumoto

Turkish Journal of Chemistry

Rare earth elements (REEs) are increasingly being used in advanced materials, but their extraction remains a major challenge. This is primarily due to their nearly identical ionic radii and similarity in chemical and physical properties. Therefore, this study aims to explore the use of a hydrophobic protic ionic liquid (PIL) composed of decanoic acid and trioctylamine (TOA) to selectively extract scandium (Sc) from other REEs using acid or salt as the extraction medium. In the acidic medium, the extraction efficiency of all tested REEs was inversely proportional to the acid concentration. Meanwhile, the extraction percentage of Sc was significantly higher …