jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Fatemeh Abbasi | Ali Reza Sardarian
Source: Royal Society Open Science (article, 2024-06-01)
Field: Chemistry — Organic Chemistry

Efficient base- and ligand-free palladium catalysed <i>O</i> -arylation of phenols in choline chloride:triethanolamine as a reusable deep eutectic solvent In this paper, we present a novel and sustainable approach using choline chloride:triethanolamine as a green, efficient and reusable deep eutectic solvent (DES) for Pd-catalysed <i>O</i>-arylation reactions with Pd/BaSO<sub>4</sub> (10%). By using the unique properties of DESs, we successfully achieved C-O bond formation without the need for additional solvents, bases and ligands. This solvent/catalyst system ([ChCl][TEA]<sub>2</sub>) functioned as a dual catalyst and solvent system, enabling fast and environmentally friendly C-O bond formation from phenol derivatives and electron-deficient aryl halides, leading to remarkable yields under mild reaction conditions. To identify and characterize this DES, we employed differential scanning calorimetry, thermogravimetric analysis, Fourier-transform infrared spectroscopy, refractive index, viscosity, the potential of hydrogen (pH) and conductivity measurements. One of the remarkable advantages of this DES system is its exceptional stability. This solvent/catalyst system exhibited high stability throughout the reaction cycles, showing no significant loss of activity. As a result, this DES and catalyst (Pd/BaSO<sub>4</sub> (10%)) can be easily recycled and re-used for up to three consecutive cycles, making it an economically and environmentally attractive option for organic reactions. Our approach offers several key benefits, including simple catalyst preparation, quick reaction times and excellent production efficiency. Triethanolamine ; Choline chloride ; Deep eutectic solvent ; Catalysis ; Chemistry ; Thermogravimetric analysis ; Solvent ; Green chemistry ; Organic chemistry ; Ionic liquid ; Eutectic system ; Inorganic chemistry Catalytic Cross-Coupling Reactions ; Catalytic C–H Functionalization Methods ; Sulfur-Based Synthesis Techniques
Authors: Haoming Zhang | Hongyu Xu | Wen Zeng | Zhongchang Wang | Qu Zhou
Source: Frontiers in Chemistry (review, 2024-11-27)
Field: Materials Science — Materials Chemistry

Gas sensing performance of Ti3C2Tx MXene heterojunction structures in greenhouse environments: a mini review With the continuous advancement of smart greenhouse technologies, digital and information-based environmental monitoring has emerged as a focal point of research. The development of high-performance gas sensors is central to achieving this objective. In recent years, MXene materials have been widely applied in the field of gas sensors due to their excellent ion mobility, favorable hydrophilicity, outstanding electronic conductivity, and unique physicochemical properties. Various MXene heterojunction structures have been synthesized for gas detection. This review aims to summarize the current state of research on Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>-based gas sensors, explore methods for synthesizing different morphologies of Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> heterojunction structures, and evaluate the sensing behaviors of these configurations to fully harness their potential for gas monitoring in greenhouse environments. Additionally, an in-depth analysis of the sensing mechanisms associated with Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> heterojunction structures will be provided, offering theoretical support for future investigations. The findings indicate that Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>-based nanomaterials demonstrate considerable promise as high-performance sensors for gas detection in greenhouse settings. This innovative research not only provides new insights into the development of gas sensor technologies but also serves as an important foundation for the digitization of environmental monitoring. Heterojunction ; Greenhouse gas ; Materials science ; Nanotechnology ; Environmental science ; Optoelectronics ; Engineering physics ; Engineering ; Ecology ; Biology MXene and MAX Phase Materials ; Advanced Memory and Neural Computing ; 2D Materials and Applications
Authors: Partha Kumbhakar | V. Kumara Vel | Ashit Kumar Pramanik | Rajesh Chaudhary | S. Prasanth | Julka Kumari Tripathi | A.K. Singh | Amreesh Chandra | Himashu Tiwary | S. P. Singh | Chandra Sekhar Tiwary
Source: Journal of Integrated Standardized Homoeopathy (article, 2024-05-30)
Field: Materials Science — Materials Chemistry

Understanding of potentization process of homoeopathic medicine of Aurum Metallicum and its characterisation Objectives: The effect of homoeopathic potentization increases with dilution. The physical and chemical properties of the homoeopathy solution change as a function of the concentration of nanoparticles (NPs). The succussion process is also vital in homoeopathy. However, none of these factors, along with the container of the medicine, have been well-researched to date. Material and Methods: We studied the systematic ultra-low dilution (up to 10 200 times) effect of homoeopathic remedy of Aurum Metallicum (Gold) NP colloidal solution to determine the mechanism of colloidal formation in such extreme dilution. Several material characterizations were also performed to consolidate our results. Results: Optical spectroscopy confirmed the presence of NPs with narrow size distribution and high surface activity in higher dilution (up to 10 200 times) homoeopathic solution. The particle size analysis of the serially diluted solution showed that the size distribution becomes narrow with increasing dilution. Transmission electron microscopy confirmed the presence of NPs in solutions up to 10 200 times dilution. Conclusion: The process of dilution introduces an active hydrocarbon layer on these NPs. The experimental study further confirmed theoretical calculations. The understanding of such extreme dilutions can be utilized in biomedical applications, especially in homoeopathic medicine. Dilution ; Serial dilution ; Homeopathy ; Materials science ; Nanotechnology ; Chemistry ; Medicine ; Thermodynamics ; Physics Nanoparticles: synthesis and applications ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Shaham Quadir | Zhenkun Yuan | Guillermo L. Esparza | Sita Dugu | John S. Mangum | Andrew Pike | Muhammad Rubaiat Hasan | Gideon Kassa | Xiaoxin Wang | Yagmur Coban | Jifeng Liu | Kirill Kovnir | David P. Fenning | Obadiah G. Reid | Andriy Zakutayev | Geoffroy Hautier | Sage R. Bauers
Source: arXiv (Cornell University) (preprint, 2024-06-21)
Field: Materials Science — Materials Chemistry

Low-Temperature Synthesis of Stable CaZn$_2$P$_2$ Zintl Phosphide Thin Films as Candidate Top Absorbers The development of tandem photovoltaics and photoelectrochemical solar cells requires new absorber materials with band gaps in the range of ~1.5-2.3 eV, for use in the top cell paired with a narrower-gap bottom cell. An outstanding challenge is finding materials with suitable optoelectronic and defect properties, good operational stability, and synthesis conditions that preserve underlying device layers. This study demonstrates the Zintl phosphide compound CaZn$_2$P$_2$ as a compelling candidate semiconductor for these applications. We prepare phase pure, 500 nm-thick CaZn$_2$P$_2$ thin films using a scalable reactive sputter deposition process at growth temperatures as low as 100 °C, which is desirable for device integration. UV-vis spectroscopy shows that CaZn$_2$P$_2$ films exhibit an optical absorptivity of ~10$^4$ cm$^-$$^1$ at ~1.95 eV direct band gap. Room-temperature photoluminescence (PL) measurements show near-band-edge optical emission, and time-resolved microwave conductivity (TRMC) measurements indicate a photoexcited carrier lifetime of ~30 ns. CaZn$_2$P$_2$ is highly stable in both ambient conditions and moisture, as evidenced by PL and TRMC measurements. Experimental data are supported by first-principles calculations, which indicate the absence of low-formation-energy, deep intrinsic defects. Overall, our study should motivate future work integrating this potential top cell absorber material into tandem solar cells. Phosphide ; Materials science ; Thin film ; Indium phosphide ; Optoelectronics ; Nanotechnology ; Metallurgy ; Metal ZnO doping and properties ; Advanced Thermoelectric Materials and Devices ; Thermal Expansion and Ionic Conductivity
Authors: Takaaki Tsuruoka | K. Araki | Kouga Kawauchi | Yohei Takashima | Kensuke Akamatsu
Source: Inorganics (article, 2024-01-01)
Field: Chemistry — Inorganic Chemistry

Direct Formation of ZIF-8 Crystal Thin Films on the Surface of a Zinc Ion-Doped Polymer Substrate Thin films of metal–organic frameworks (MOFs) on polymer substrates and MOF/polymer mixed-matrix membranes play crucial roles in advancing the field of gas separation membranes. In this paper, we present a novel method for the direct formation of continuous ZIF-8 crystal films on a polymer substrate doped with Zn²+. Our approach involves ion exchange between the doped zinc ions within the substrate and sodium ions in the presence of a CH3COONa additive, as well as interfacial complexation with eluted zinc ions and 2-methylimidazole (2-MeIM). The key factors affecting the formation of ZIF-8 crystals on the substrate were the concentrations of CH3COONa and 2-MeIM. A time-course analysis revealed that the nucleation rate during the early stages of the reaction significantly affected the surface morphology of the resulting ZIF-8 crystal films. Specifically, a higher nucleation rate led to the formation of continuous small ZIF-8 crystal films. This innovative approach enables the fabrication of densely packed, uniform ZIF-8 crystal films. Nucleation ; Zinc ; Materials science ; Substrate (aquarium) ; Chemical engineering ; Membrane ; Polymer ; Crystal (programming language) ; Thin film ; Doping ; Inorganic chemistry ; Ion exchange ; Ion ; Nanotechnology ; Chemistry ; Organic chemistry ; Composite material ; Metallurgy Metal-Organic Frameworks: Synthesis and Applications ; Membrane Separation and Gas Transport ; Covalent Organic Framework Applications
Authors: Krishnamoorthy Rajavel | Suprem R. Das
Source: Applied Research (article, 2024-01-12)
Field: Materials Science — Materials Chemistry

Inkjet‐printed flexible <i>MXetronics</i> : Present status and future prospects Abstract Over the past several years, atomically thin two‐dimensional carbides, nitrides, and carbonitrides, otherwise known as MXenes , have been expanded into over fifty material candidates that are experimentally produced, and over one hundred fifty more candidates that have been theoretically predicted. They have demonstrated transformative properties such as metallic‐type electrical conductivities, optical properties such as plasmonics and optical nonlinearity, and key surface properties such as hydrophilicity, and unique surface chemistry. In terms of their applications, they are poised to transform technological areas such as energy storage, electromagnetic shielding, electronics, photonics, optoelectronics, sensing, and bioelectronics. One of the most promising aspects of MXene's future application in all the above areas of interest, we believe, is reliably developing their flexible and bendable electronics and optoelectronics by printing methods (henceforth, termed as printed flexible MXetronics ). Designing and manipulating MXene conductive inks according to the application requirements will therefore be a transformative goal for future printed flexible MXetronics. MXene's combined property of high electrical conductivity and water‐friendly nature to easily disperse its micro/nano‐flakes in an aqueous medium without any binder paves the way for designing additive‐free highly conductive MXene ink . However, the chemical and/or structural and hence functional stability of water based MXene inks over time is not reliable, opening research avenues for further development of stable and conductive MXene inks. Such priorities will enable applications requiring high‐resolution and highly reliable printed MXene electronics using state‐of‐the art printing methods. Engineering MXene structural and surface functional properties while tuning MXene ink rheology in benign solvents of choice will be a key for ink developments. This review article summarizes the present status and prospects of MXene inks and their use in inkjet‐printed (IJP) technology for future flexible and bendable MXetronics . MXenes ; Nanotechnology ; Electronics ; Materials science ; Electrical conductor ; Printed electronics ; Photonics ; Flexible electronics ; Transformative learning ; Inkwell ; Optoelectronics ; Electrical engineering ; Composite material ; Engineering MXene and MAX Phase Materials ; Advanced Sensor and Energy Harvesting Materials ; Advanced Memory and Neural Computing
Authors: Sayan Basak | Kevin A. Cavicchi
Source: Journal of Polymer Science (article, 2024-11-14)
Field: Materials Science — Polymers and Plastics

Comparison of Swollen vs. Compounded Cross‐linked High‐<i>Cis</i>‐1,4‐Polybutadiene/<i>n</i>‐Tetracosane Shape Memory Polymers ABSTRACT Blending elastomers with phase change materials offers a modular approach to fabricating smart materials, such as shape memory polymers. This study compares shape memory polymers prepared by peroxide cross‐linking a blend of polybutadiene and n ‐tetracosane (compounded samples) versus swelling peroxide cross‐linked polybutadiene in n ‐tetracosane (swollen samples). Characterization of the thermal, thermomechanical, and shape memory behavior of the two types of samples show very similar behavior as a function of polybutadiene content. The sample with ca. 30% polybutadiene displayed shape memory metrics of ~90% fixity and ~99% recovery at 25% applied strain. The main difference in the samples was the change in fixity and recovery with cycling where they were heated and cooled using water baths. The compounded samples exhibited a 1.4% decrease in fixity, 0.2% decrease in recovery, and 2.25% weight loss over 20 cycles. In contrast, the swollen samples have a 4.2% decrease in fixity, 0.4% decrease in recovery, and 5.63% weight loss over 20 cycles. This weight loss was attributed to the expulsion of the n‐ tetracosane that experienced a higher driving force in the swollen sample with stretched chains. The cyclic and long‐term aging of these polymers is different depending on the preparation method to incorporate the n ‐tetracosane into the material. Polybutadiene ; Polymer ; Polymer science ; Copolymer ; Polymer chemistry ; Materials science ; Chemistry ; Composite material Polymer composites and self-healing ; Photochromic and Fluorescence Chemistry ; Marine Sponges and Natural Products
Authors: Cem Cüneyt Ersanlı | Sultan Başak
Source: International Scientific and Vocational Studies Journal (article, 2024-12-28)
Field: Chemistry — Spectroscopy

Quantum Mechanical Calculations and Molecular Docking Simulation Studies of N-(5-chloro-2-oxobenzyl)-2-hydroxy-5-methylanilinium Compound Schiff bases were first synthesized by Hugo Schiff in 1864. The formation of a carbon-nitrogen double bond is what gives specificity to Schiff bases. This double bond is referred to as an imine (R-N=C-R). This double bond contributes to the high activity of Schiff bases, allowing for extensive research across various fields and disciplines. Neurodegenerative diseases are conditions that continuously and irreversibly affect neurons and nerve cells in the central nervous system, and they are among the leading causes of death in developed countries. Alzheimer’s disease, which is a type of neurodegenerative disease, currently has about 5 million new cases each year, and there is no definitive and complete treatment method for it. Individuals with this disease exhibit symptoms such as memory loss, inability to form new memories, and slowing of cognitive functions. Additionally, these patients show imbalances in neurotransmitters responsible for facilitating neural transmission between neurons, particularly an irreversible loss of cholinergic neurons, which are a significant part of the central nervous system. Disruption of homeostasis in the mechanisms of acetylcholinesterase (AChE) and monoamine oxidase (MAO) neurotransmitters is indicated among the causes of Alzheimer’s disease. In this study; the physical, chemical and biological properties of N-(5-chloro-2-oxobenzyl)-2-hydroxy-5-methylanilinium molecule were investigated by quantum mechanical calculation methods. In support of the X-ray results, the geometrical parameters (bond lengths, and bond angles) and quantum chemical properties of the title compound were theoretically realized by the density functional theory method with B3LYP/6-311G(d,p) basis set using Gaussian 03W program. Herein, Frontier orbitals, molecular electrostatic potential surface, nonlinear optical properties, natural bond orbital analysis, Mulliken charges, and Hirshfeld surface analysis of the title compound were also calculated to explain the intermolecular interactions. Additionally, molecular docking results were performed with AChE and MAO-B enzymes obtained from the Protein Data Bank (PDB). All these studies have shown that the structure has high stability and forms a strong bond with the relevant enzymes. Physics Molecular spectroscopy and chirality ; Advanced NMR Techniques and Applications ; Pharmacological Receptor Mechanisms and Effects
Authors: Eldar Miftakhov | Sofia Mustafina | А. А. Akimov | Светлана Мустафина
Source: e-Polymers (article, 2024-01-01)
Field: Chemistry — Inorganic Chemistry

Simulation approach to study kinetic heterogeneity of gadolinium catalytic system in the 1,4- <i>cis</i> -polyisoprene production Abstract This article presents a novel simulation approach for solving the inverse problem of kinetic heterogeneity in polymerization processes, specifically focusing on the production of polyisoprene using a gadolinium chloride solvate-based catalytic system. The proposed method is based on the assumption that the distribution of active centers (ACs) can be described by model distributions. By utilizing primary physicochemical data, such as the polymerization rate and molecular weight distribution, the simulation approach automatically identifies the kinetic parameters, determining the Frenkel statistical parameter and solving the problem of kinetic heterogeneity. The experimental results revealed the presence of at least three distinct types of ACs, each contributing different proportions to the polymerization process. The simulation approach offers valuable insights into the complexities of catalytic systems and their role in polymerization, paving the way for optimizing reaction conditions and advancing industrial polymer synthesis processes. This study marks a significant step forward in understanding and controlling polymerization reactions, with potential implications for the development of innovative materials and industrial applications. Gadolinium ; Kinetic energy ; Catalysis ; Production (economics) ; Kinetics ; Chemistry ; Biochemistry ; Economics ; Physics ; Organic chemistry ; Microeconomics Zeolite Catalysis and Synthesis ; Catalytic Processes in Materials Science ; Advanced Data Processing Techniques
Authors: Loredana Schiavo | Lucrezia Aversa | Roberto Verucchi | Rachele Castaldo | Gennaro Gentile | G. Carotenuto
Source: Ceramics (article, 2024-03-23)
Field: Materials Science — Materials Chemistry

Negative Temperature Coefficient Properties of Natural Clinoptilolite Negative temperature coefficient (NTC) materials are usually based on ceramic semiconductors, and electrons are involved in their transport mechanism. A new type of NTC material, adequate for alternating current (AC) applications, is represented by zeolites. Indeed, zeolites are single charge carrier ionic conductors with a temperature-dependent electrical conductivity. In particular, electrical transport in zeolites is due to the monovalent charge-balancing cations, like K+, capable of hopping between negatively charged sites in the aluminosilicate framework. Owing to the highly non-linear electrical behavior of the traditional electronic NTC materials, the possibility to have alternative types of materials, showing linearity in their electrical behavior, is very desirable. Among different zeolites, natural clinoptilolite has been selected for investigating NTC behavior since it is characterized by high zeolite content, a convenient Si/Al atomic ratio, good mechanical strength due to its compact microstructure, and low toxicity. Clinoptilolite has shown a rapid and quite reversible impedance change under heating, characterized by a linear dependence on temperature. X-ray diffraction (XRD) has been used to identify the natural zeolite, to establish all types of crystalline phases present in the mineral, and to investigate the thermal stability of these phases up to 150 °C. X-ray photoelectron spectroscopy (XPS) analysis was used for the chemical characterization of this natural clinoptilolite sample, providing important information on the cationic content and framework composition. In addition, since electrical transport takes place in the zeolite free-volume, a Brunauer–Emmett–Teller (BET) analysis of the mineral has also been performed. Clinoptilolite ; Natural (archaeology) ; Temperature coefficient ; Materials science ; Environmental science ; Chemistry ; Composite material ; Geology ; Zeolite ; Organic chemistry Thermal and Kinetic Analysis ; Chemical Thermodynamics and Molecular Structure ; thermodynamics and calorimetric analyses
Authors: Najmeh. Anvari | Morteza Ghorbanzadeh Ahangari | Mohsen Jahanshahi | Sajjad Dargahi
Source: Preprints.org (preprint, 2024-06-11)
Field: Materials Science — Materials Chemistry

Probing Methanol Adsorption on Two-Dimensional Nanopar-ticles: A Comprehensive Density Functional Theory Study In this research, we utilize density functional theory (DFT) to study and investigate the adsorption process of methanol on three unique two-dimensional nanomaterials, namely BN, Graphene, and AlN. Eight sites for BN, AlN, and six sites for graphene were considered to reach full structural optimization. By conducting comprehensive simulations and analyses, we discovered diverse adsorption configurations and energy levels, which indicate different interaction strengths between methanol and the three 2D nanomaterials. Remarkably, AlN exhibits superior adsorption capabilities when compared to Graphene and BN which can be explained by attributable to the nature of charge transfer between the adsorbate and the adsorbent. For methanol adsorption on AlN, the strongest adsorption energy was (-0.5532 eV), and the amount of charge transferred from methanol to AlN was found to be (+0.075). For BN, the strongest adsorption energy was (-0.1351 eV), and the amount of charge transferred from methanol to BN was (+0.022). The density of states results indicated that the bandgap decreased, with a shift to the right. In contrast, for methanol adsorption on graphene, the strongest adsorption energy was found to be (-0.073 eV), and the amount of charge transferred from methanol to graphene was (+0.004). The density of states results showed no change in the bandgap. Our findings underscore the superiority of AlN’s potential over BN and Graphene for applications requiring efficient methanol adsorption, such as gas separation and storage technologies. This study emphasizes the superiority of AlN over Graphene and BN for tasks that necessitate effective methanol adsorption. Graphene ; Adsorption ; Methanol ; Density functional theory ; Materials science ; Nanomaterials ; Band gap ; Density of states ; Chemical physics ; Binding energy ; Chemical engineering ; Nanotechnology ; Computational chemistry ; Physical chemistry ; Chemistry ; Atomic physics ; Condensed matter physics ; Organic chemistry ; Optoelectronics ; Physics Graphene research and applications ; 2D Materials and Applications ; Boron and Carbon Nanomaterials Research